Introduction
After the Fourth Crusade of 1204, a collection of successor states to the Byzantine Empire popped up around the Aegean basin, shattering the tradition of unified government that had prevailed since the time of the Roman Republic. The result was devastating conflict on all parts. Yet due to the genius of two of the emperors of Nicaea, one of the successor states - John III Ducas Vatatzes and Michael VIII Palaeologus - the Nicene Emperors recovered Thrace, much of Greece, and the imperial capital of Constantinople itself, seized in 1261. After Michael VIII, the rule of Andronicus II was fraught with territorial losses and thoroughly mediocre government, culminating in a civil war with his grandson, Andronicus III, which lasted seven years and seriously weakened imperial holdings in western Anatolia.
Andronicus III's reasonably skilled leadership - combined with that of his grand domestic [1] John Cantacuzenus - won more for the Empire than it lost during the 1330s, but his premature death sparked a civil war that ended up prostrating the Byzantine state. By its end, the Empire was open to plague and to its neighbors from without, and wracked by social and theological tensions within. Before the death of Andronicus III, Byzantium had a future; after, its doom was nearly certain.
The Victories of Andronicus III
Andronicus III early on grasped that the new emirate of the Ottoman Turks, led by its second recorded ruler, Orhan, was a serious threat. Under Ottoman assault, Byzantine Anatolia was in far more danger than any of his other holdings. Upon taking charge in 1328 he immediately dealt with what problems cropped up in Europe (namely, Michael III Shishman of Bulgaria's attack on Adrianople) then prepared to set off with Cantacuzenus to relieve Nicomedia and Nicaea, both under siege. At Pelecanum in 1329, on the road to Nicomedia, the Byzantine army scored some early successes against the Ottoman blockaders but after inconclusive skirmishing began to withdraw; the Ottomans fell upon the Byzantines, but Cantacuzenus managed to ward them off until the army was able to be ferried back across the straits to Europe. Seeing that Byzantine power alone would be unable to smash the new Ottoman dynamo, Andronicus elected to find some allies. The Emirate of Aydin and the Emirate of Saruhan were both persuaded to join the Empire as a counterbalance to the Turks. To bolster his position in the Aegean, Andronicus had the island of Chios seized from the Genoese when its populace revolted.
Stephen III of Serbia, taking advantage of Andronicus' absence in the East, had made an attack on Ochrid; Andronicus had Cantacuzenus drive him off, and then made a pact with his old enemy Shishman of Bulgaria to launch a combined assault on the Serbians. In 1330, though, the Serbians attacked Bulgaria first and killed Shishman in battle. Seeing his enemy's weakness, Andronicus pragmatically patched up relations with the Serbs and struck into Bulgaria, seizing the Greek coastal cities of Mesembria and Anchialus. Now that Bulgaria seemed prostrate, Andronicus thought he had time to turn his attention back to the east, and was pleased to be invited to take part in a Holy League in 1332 with the Knights Hospitaller and Venice against the Turks. However, the Hospitallers and the Venetians wanted to attack Aydin, for Aydin was threatening coastal possessions of the Venetians in Anatolia, and Andronicus wasn't quite prepared to abandon his ally against the Ottomans, especially when the Ottomans had just seized Nicaea following a long siege. Andronicus, however, rated an opportunity to initiate negotiations for church union higher than he rated an alliance with the emir of Aydin, and so acceded to the Holy League charter and made a truce with Orhan in 1333, paying tribute in order to keep the Ottomans out of Nicomedia.
In 1333 the territory of Thessaly was left without a ruler after the inopportune death of its current one; Byzantium and the Despotate of Epirus, under John Orsini, made a mad dash to secure what they could of the prize. Andronicus had the bigger army, and upon arrival there in the autumn smashed Orsini's occupying force and conquered the whole territory, winning a major victory. At the same time, though, Andronicus lost Ochrid to the new Serbian king, Stephen IV Dushan. But Byzantium was able to win big in another area. Andronicus' preoccupation with Thessaly had prevented him from making his contribution to the Holy League, which set sail anyway and destroyed much of the Aydin fleet. The Genoese, now rid of their perpetual tormentors, decided to get revenge for the loss of Chios and attacked Byzantine possessions in the Aegean. And since Andronicus had not participated in the attack on Aydin, he was able to ally with them against the Genoese. Cantacuzenus was dispatched to Anatolia to sign a pact with Umur Bey, the emir, and with Umur's aid the Genoese were smashed and even forced to yield Phocaea, on the Anatolian coast.
In 1337 dynastic troubles in Epirus following the assassination of John Orsini allowed the Byzantines to make book. While the intervention prevented Andronicus from punishing Orhan for violating his treaty and capturing Nicomedia, it did allow Cantacuzenus to crush an Albanian revolt and follow it up with an invasion of Epirus itself, which collapsed and was seized in its entirety. Cantacuzenus was able to consolidate Byzantine rule and smashed an Epirote revolt at Arta in 1339. With this success, the Latin barons of central and southern Greece offered their vassalage to the emperor, so long as they were treated well.
However, there were ominous clouds on the horizon, even after the brilliant seizure of Epirus. The participation in the Holy League had allowed for negotiations with the Western Church for union, but the theological debates that ensued proved unfortunate. At the talks, a monk of Mount Athos, Gregory Palamas, brought up the practice of hesychasm, which was a rite done by his fellow monks that, the monks believed, enabled them to see the light around God Himself. Barlaam of Calabria, another of the Greek delegates, claimed that this was lunacy, and that mysticism was incomparable to philosophical thought in terms of the ability to know God. Theoretically the matter was settled when Barlaam's accusations of heresy were rejected and a gag rule put in place, in 1341. But church union was still proving a tough nut to crack.
In that year, in the month of June, Andronicus III fell sick and died within a few days. He was forty-four years old. Things at the end of his reign seemed bright. He had secured Thessaly and Epirus, even if the last shreds of Byzantine Bithynia had been lost, and possessions were retained and even expanded in the Aegean. Best of all, his general Cantacuzenus was still alive and well, the main architect of his success, and surely he would become regent for Andronicus' young son John V.
The Beginnings of Civil War
John Cantacuzenus had been named by Andronicus as a regent for his as-yet unborn son in 1330, when Andronicus had been extremely sick and fearful of death. He expected to be awarded this position in the summer of 1341, with good reason. Cantacuzenus already had command of much of the bureaucracy, and things largely kept humming as they usually did, but made certain to refrain from having the Patriarch crown him coemperor, as the grand duke [2] Alexius Apocaucus advised.
The death of Andronicus, who had been perceived as a strong emperor during his thirteen years on the throne, set off threats from the neighboring powers. Stephen Dushan renewed his attack on Byzantine Macedonia, another Albanian revolt erupted, John Alexander of Bulgaria threatened to take revenge for the loss of Mesembria and Anchialus, and Turkish pirates attacked the Thracian coast. In addition, the Latin barons had to be accommodated to make bank in Greece, and Cantacuzenus had in his possession a candidate for the throne of the Empire of Trebizond, a Greek state in northern Anatolia, whom he wanted to use to exert political influence there. As Cantacuzenus prepared to take on all of these problems, he quickly convened a synod on Palamism, the debate over hesychasm, and had Palamas' main opponent Gregory Acindynus condemned. He then broke up the pirate attacks and intimidated the Bulgarians and Serbs into making peace, and accepted the submission of the Latins. It was an excellent start.
His power was soon forgotten by his enemies in the capital. Alexius Apocaucus, the empress-mother Anna, and the Patriarch, John Calecas, were all plotting to take control of the regency. Apocaucus, however, made too much noise, and Cantacuzenus came back to Constantinople in August and had him imprisoned. On the empress' request, though, Apocaucus was released. Cantacuzenus was apparently unaware of her complicity, and anxious to have an ally in the city. Next month he started off towards southern Greece to formally impose Greek administrators on the Peloponnese and install detachments from the Byzantine army. In his absence, things got much worse.
Cantacuzenus had the misfortune to be one of the largest landowners in the Byzantine state. His family estates, mostly around Didymotichus in Thrace, aroused a great deal of envy. In addition, they were symbolic of the creeping gains that the landowning elites had made since the days of relative meritocracy during the Macedonian dynasty centuries before. Cantacuzenus and his fellow magnates were facing constant opposition by merchants and tradesmen. Apocaucus elected to make use of this factor in support of his rival regency. He allied with the Patriarch and the empress-mother Anna, and led mobs in ransacking Cantacuzenus' house in the capital. Anna then fired Cantacuzenus from his job as grand domestic. The general, understandably enraged but with his army still in Thrace, had himself declared co-emperor and gave up on the Peloponnese.
John VI, Cantacuzenus, had the main army, but his opponents in the Regency held the capital, and they had a significant symbolic advantage in actually controlling the person of the rightful emperor, John V. Cantacuzenus was abandoned by some of his natural allies, the big magnates, because of these strikes against him. At the same time, Apocaucus did his best to incite the urban poor to rise up against landowners who supported the pretender. When John VI left Didymotichus to seize Adrianople, first city of Thrace, he managed to convince some of the burghers and main municipal officials to declare for his side. But Apocaucus had the patriarch excommunicate Cantacuzenus and sent his son Manuel to incite an urban riot and drive out the burghers, denying the pretender his prize. Manuel was made governor of the city, and fortified it well enough to prevent John VI from successfully capturing it. As a wave of urban violence swept across Thrace, Cantacuzenist city councils were imprisoned or driven out, and Cantacuzenist garrisons were expelled and slaughtered. All John VI had the ability to do that autumn was prevent John Alexander of Bulgaria from capturing Adrianople, somewhat altruistically, but he himself could do no better. By the end of the year 1341, John VI was left with only a slice of the Thracian countryside, as the Regency commanded the loyalty of most of the cities. Thessaly and Epirus, which had been conquered by Cantacuzenus himself not so long ago, refused to declare a side.
In 1342 Cantacuzenus smelt an opportunity: the governor of Thessalonica promised to give his city up despite having publicly declared for the Regents. All John VI needed to do was appear at the city walls with an army. The pretender lost no time, and brought the bulk of his army down the Hebrus valley to the city, but even at his fastest pace was unable to get there fast enough. The Thessalonican mob heard rumors of his approach and of the governor's infidelity, and led by Apocaucus' other son John they overthrew the governor. They called their city government the 'Zealots' and promptly set about slaughtering any magnates within the walls. John VI was met with an implacable, popularly motivated resistance upon his arrival beneath the walls of Thessalonica, and was forced to withdraw. He met another diplomatic defeat when Michael Comnenus, his candidate at Trebizond, was expelled in favor of John III Comnenus, who was a partisan of Apocaucus and the Regency.
The War Widens
That summer, John VI elected to seek help from the only remaining place he saw it: Stephen Dushan of Serbia. At a personal meeting in southern Serbia, Dushan set his own terms. He would aid John VI in claiming his proper place on the throne, in exchange for the ability to keep any conquests he made from the Regents. John VI, too, had unleashed a dangerous force, but he felt he had no choice, met with insuperable resistance at every turn. The summer did not end well for the pretender, for his initial assault on the Regency fortress of Serres met with failure due to an outbreak of dysentery in his camp, and he was forced to pull back to Serbia. Stephen Dushan, on the other hand, gleefully seized Castoria and Edessa with little trouble.
Cantacuzenus finally managed a major success in the autumn of 1342, when Thessaly, long on the fence, came over to his side and accepted his governor. Not a small part was played in the decision by the approach of Stephen Dushan. The Greek Thessalians wished to avoid the reimposition of foreign rule and so the scales were tipped to Cantacuzenus. Temporarily blocked off from his ambitions, Dushan retired for the winter. At the same time, Cantacuzenus' wife, Irene, was able to hold out at isolated Didymotichus, aided by a rogues' gallery of allies: John Alexander of Bulgaria, who wished to keep the civil war going as long as possible, and Umur Bey of Aydin, loyal to his old friend Cantacuzenus, who sailed a fleet up the Hebrus before winter's onset forced him to return to Anatolia.
The Regency's hold on the western Empire totally collapsed in early 1343, when Cantacuzenists seized control of the Epirote government and received troops from the pretender, and Albania was conquered by Dushan. The threat of Serbian dominion was enough to push the key city of Beroea into Cantacuzenist hands, too. Things were looking up as John VI brought an army together to besiege Thessalonica. But his success invited opposition. Stephen Dushan was not satisfied with his Albanian and Macedonian gains, and further ones could only be made at John VI's expense. He abruptly switched sides, timed with the arrival of Alexius Apocaucus with a relieving army at Thessalonica. Met with these twin attacks, Cantacuzenus retired into his new Thessalian stronghold and sent for help from Umur Bey. Leaving his son Manuel Cantacuzenus in charge at Beroea, he set off with Turkish troops to relieve his wife at Didymotichus. In early summer, he finally succeeded, and Irene Cantacuzena's exhausted supporters were finally allowed rest. Umur Bey sent his troops to plunder the Regency-controlled parts of the Thracian countryside as his Cantacuzenist allies caught their breath.
To gain extra support, the Regents decided to take a theological approach. The Empress-mother Anna pawned the crown jewels to Venice, and tried to get the Venetians to resurrect the Holy League to renew attacks on Aydin. She also took the opportunity to imprison Gregory Palamas and declare for his opponents, for the sake of getting credit with the Western Church. Anna also personally submitted to papal authority. This, and the departure of Umur's troops, allowed the Regents a good shot at smashing the Cantacuzenist forces in 1344. Bulgaria and Serbia joined Apocaucus for a multipronged strike at the pretender. John VI brilliantly repelled the Serbians with the remainder of his Turks from Aydin. He then linked up with Manuel at Beroea and smashed Alexius Apocaucus' army, aided by the failure of John Alexander to come to his allies' aid. The Bulgarians had contented themselves with occupying Philippopolis, and thus didn't figure into Cantacuzenus' calculations at all. John Alexander did not oppose the pretender as his army marched into eastern Thrace. Rats began to flee the sinking Regency ship; even Apocaucus' son Manuel, putative governor of Adrianople, fled his city for the Cantacuzenist camp.
Cantacuzenus took two minor hits in the fall of 1344. One was the decisive defeat of Umur Bey's forces in Aydin. The Venetians smashed his fleet and captured Smyrna, even with the reinforcements that Umur had brought from Europe. The second was Manuel Apocaucus' failure to bring over Adrianople. Zealot mobs had seized control of the city, and when Cantacuzenus drew up his army underneath its walls, it was rebuffed. John VI sat down to a siege over the winter. At least now he was strong enough to fight without Turkish reinforcements. As he blockaded Adrianople, Anna and the Regents began to purge the capital of suspected Cantacuzenist collaborators, excommunicating the jailed Gregory Palamas and inciting mobs that attacked theological and class enemies.
The Cantacuzenist Victory
In 1345, Cantacuzenus was joined by two allies: Umur Bey of Aydin, who had managed a brilliant trap in the Smyrna harbor and captured much of the Holy League fleet, and the Ottomans of Orhan, who figured out which of the two Byzantine sides liked Turks better. Adrianople surrendered even before the Turks got there, and the Zealots were duly purged. With Ottoman reinforcements, John VI was even able to march to the Black Sea coast, tightening the noose around the capital. He prepared to march on Serres, a Regency city besieged by the Serbs, to relieve it and perhaps convince the city council to switch to his side. News of Alexius Apocaucus' death, lynched while stupidly hanging out with his aristocratic prisoners, induced him to abandon the Serres drive and make for Constantinople. He failed to capture it, for John Calecas and Anna had things well in hand. He also was unable to secure Thessalonica despite the defection of its governor, John Apocaucus. Apocaucus' betrayal got him the enmity of the Zealots, who had him murdered and who then assumed control of the city. Still, the two remaining Regents were confined to the capital and Thessalonica now. The war was clearly entering its endgame.
But that did not mean that the other participants were finished fighting over the spoils. Stephen Dushan seized control of Serres and then marched straight down to the Aegean coast, conquering the Chalcidice and Mount Athos. The Byzantine Empire was cut in two. To celebrate, Dushan crowned himself emperor in 1346, and John Alexander elevated himself to the same rank so as not to be outdone. Cantacuzenus, learning of the new titles, was spurred to secure his own crown. At Adrianople, the exiled Patriarch of Jerusalem officially made him John VI, though only as co-emperor with John V. John VI also held a council at Adrianople that reaffirmed support for Palamism and deposed John Calecas at Jerusalem. The Regency tried a last few blows, hiring Turks from Saruhan, but they deserted to Cantacuzenus after a short period of pillaging. Anna also lost Chios and Phocaea to the Genoese, who were anxious to make some progress since they had failed against Umur Bey.
John Calecas was proving to be one of the final impediments to the end of the war, so Anna had him deposed in February 1347, then opened negotiations with John VI. He promptly infiltrated a thousand of his men, with himself at their head, into Constantinople to make the negotiations go more smoothly. Anna agreed to a power-sharing arrangement, whereby John VI would be senior emperor until John V came of age, solidifying the whole thing by marrying John V to Helena Cantacuzena, John VI's daughter. John VI also married off another daughter, Theodora, to Orhan, confirming that alliance as well. All land, too, was to be returned to its original owners (within what was left of the empire). John VI had finally managed his victory after more than five years.
The victory seemed hollow, though. Stephen Dushan was so far the biggest winner, having conquered copious border regions and split the empire in twain. John Alexander had had modest gains, capturing Philippopolis. Genoa had also regained all she had lost to Andronicus III. Thrace was in ruins, from both Turkish depredations and social warfare. There was practically no money left in the treasury. And the Zealots still retained Thessalonica. But there still was some brightness left. Epirus and Thessaly, the great conquests of Andronicus III and Cantacuzenus, were still under Byzantine control. John VI now had an excellently trained army, and he himself was a solid professional leader, ready to win back territory from the Serbs and Bulgarians. Dushan's gains were many, but his means were few. Byzantium still had a chance.
The Renewal of the Civil War
What ruined that chance was the Black Death. Cantacuzenus had been crowned, and was busily threatening Stephen Dushan with war unless he returned Beroea and Serres, which would thus reunite the Empire, when the plague arrived in the spring of 1347. Dushan had been equivocating, attempting to hold off fighting for as long as he could, sure that he would be unable to hold what he had seized; he was gratified by the abrupt prostration of his great enemy and immediately began a drive on Epirus. John VI, suddenly bereft of his trained army and his tax revenues truncated by the demographic disaster the Byzantine Empire was undergoing, desperately applied to help from all of his allies. The Turks were the only ones that sent any aid at all, namely ten thousand men from Orhan, but they only made things worse, failing to march against the Serbs at all and instead pillaging Thrace (again) and then returning to Asia without having fought at all. Umur died in 1348 before his own expedition was able to set sail, wounded in a battle with the Holy League.
Cantacuzenus indomitably struggled on, lowering customs duties to lure traders away from Galata, the Genoese trading colony, and amassing an army and a navy that strained his fiscal resources to the breaking point. Genoa could hardly be expected to simply allow commercial warfare with impunity, though, and promptly burned Cantacuzenus' small fleet at anchor and attacked what merchantmen were in the harbors at Constantinople to intimidate them. John VI grimly defeated what Ottoman troops were left in Thrace and besieged Galata by land. His second fleet was destroyed in battle with the Genoese, but the third was a menace they could not ignore, and if only to allow business to resume the Genoese ended the war, offering a lump sum, a ten year lease on Chios and its eventual cession to the Empire. John VI captured Phocaea for good measure. Cantacuzenist supporters also came out on top in Trebizond, and when the Serbians approached Thessalonica in 1350 after having overrun Epirus and Thessaly, the Zealots finally ended their class-warfare opposition to Cantacuzenus and asked for help. A two-pronged attack, with the emperors moving by sea and Matthew Cantacuzenus, the emperor's son, moving by land, succeeded, and inconclusive skirmishing resulted in eastern Macedonia before Dushan and Cantacuzenus agreed to a peace of mutual exhaustion.
Even this was not the end of John VI's troubles. He had set Manuel up as a ruler in the Peloponnese, accepting the suzerainty of a few of the complaint Latin barons (the rest had reneged) and gave Matthew extraordinary powers over Thrace. But in 1352 John V attacked Matthew Cantacuzenus, and threatened to renew the Zealotic class warfare. Matthew was forced back to the citadel, and only saved when his father brought in more Turks to relieve the city. A second civil war began, this time with John V fighting on his own behalf. John V was able to coax Dushan and John Alexander to send him troops and got a loan from the Venetians. Cantacuzenus called on Orhan and received more men. The two armies clashed on the Hebrus River in 1352, where John VI's tactical acumen resulted in a crushing Cantacuzenist victory. John V fled first to Tenedos, then to Thessalonica, where he was able to hold out with his mother. Now more troubles damaged the Cantacuzenist cause. Attempting to have Matthew crowned in place of John V, John VI was unable to find compliant clergy, and was at the same time unable to reduce Thessalonica. His Turks began to rampage out of control in Thrace, and amassed significant pillage; in desperation, John VI offered them ten thousand hyperpyra [3] to leave Europe. An unlucky earthquake knocked down the walls of nearby Callipolis while the Turks were considering the offer, and with Sulayman at their head they occupied the town and refused to yield it to John VI. Orhan failed to respond to Cantacuzenus' desperate missives to give up the town in exchange for the gold. The Turks, who had seized all Anatolia, were now in possession of European territory.
John V made his move then, sailing to the capital and inciting one last urban revolt. John VI, confronted with an out of control uprising, agreed to reinstate John V and abandon the cause of his son. Less than two weeks passed before he abdicated the throne himself to become a monk. The civil wars were finally over.
What Was Left of Byzantium
Evaluating the social impact of the great civil war must be done with care. The urban poor themselves had little beef with the Cantacuzenist magnates. If the nobles oppressed anybody - well, when they oppressed anybody - it was on their own estates, not in the cities. The urban poor sided with the people who did oppress them, with the merchants and tradesmen and bureaucrats. This was no simple squabble of rich and poor. But there was a significant social element in the fighting, for in many ways the civil war was an outgrowth of the old, hundreds of years old conflict between the middle classes and the landowners. The meritocratic system that obtained in the later Macedonian dynasty, especially under Basil II, was no longer in evidence. The Comneni had actually increased the power of the magnates by the system of military pronoia grants that they had imposed in the eleventh and twelfth centuries, and the system continued to work to the landlords' favor in the fourteenth. Generally, the aristocracy could rely on the aid of the monks, the anti-Westerners, and the Palamites, whose monasteries received a great deal of money from aristocratic grants. Since Italians were necessary for trade, foreigners sided with the regency and the middle classes, as well as the anti-Palamites. But even then, more immediate concerns could overturn those loyalties, and things were not always that clear cut on the ground.
John VI's short reign and his civil wars were the beginning of the end. First the destructive conflict that laid the Empire bare to the ravages of its neighbors, then the plague that prevented a response, and finally the renewal of the civil war prostrated the state and left it without much hope. What had been feared for nearly three centuries had come to pass, too, and the Turks had finally circumvented the Straits and placed themselves in control of a gateway into Europe. They had done so invited by a Byzantine Emperor and paid at his behest. But despite the calamity that befell the Byzantine state during his time, Cantacuzenus was not a bad emperor. He showed skill during the first and second civil war, and weathered many calamities, including the devastation of the Black Death. But without the revenues he had been able to obtain before the plague, or his army, he could not repel all of his enemies or keep his Turks on a leash.
Footnotes
[1] = megas domestikos = commander of the army.
[2] = megas doux = commander of the navy.
[3] = the gold currency of the Byzantine Empire.
Sources
John VI Cantacuzenus' History is one of the main sources for this period. He provides a fine narrative for the civil war from his own perspective, though one must of course be careful of bias.
Nicephorus Gregoras' Roman History also covers this period, though in far less detail, and can be used to correct Cantacuzenus when he tends to glorify his own actions.
Nicol, Last Centuries of Byzantium extends the Treadgold narrative and has recently been revised with aid from modern scholarship. On the Civil War itself it is nigh invaluable.
Treadgold, A History of the Byzantine State and Society was fantastic for these purposes. It's a very good and in depth study of the Empire as a whole, using modern scholarship instead of the older, Gibbonesque studies that obtained previously, and its incisiveness does not diminish as it moves beyond the apogee of Byzantine power. Excellent book.
After the Fourth Crusade of 1204, a collection of successor states to the Byzantine Empire popped up around the Aegean basin, shattering the tradition of unified government that had prevailed since the time of the Roman Republic. The result was devastating conflict on all parts. Yet due to the genius of two of the emperors of Nicaea, one of the successor states - John III Ducas Vatatzes and Michael VIII Palaeologus - the Nicene Emperors recovered Thrace, much of Greece, and the imperial capital of Constantinople itself, seized in 1261. After Michael VIII, the rule of Andronicus II was fraught with territorial losses and thoroughly mediocre government, culminating in a civil war with his grandson, Andronicus III, which lasted seven years and seriously weakened imperial holdings in western Anatolia.
Andronicus III's reasonably skilled leadership - combined with that of his grand domestic [1] John Cantacuzenus - won more for the Empire than it lost during the 1330s, but his premature death sparked a civil war that ended up prostrating the Byzantine state. By its end, the Empire was open to plague and to its neighbors from without, and wracked by social and theological tensions within. Before the death of Andronicus III, Byzantium had a future; after, its doom was nearly certain.
The Victories of Andronicus III
Andronicus III early on grasped that the new emirate of the Ottoman Turks, led by its second recorded ruler, Orhan, was a serious threat. Under Ottoman assault, Byzantine Anatolia was in far more danger than any of his other holdings. Upon taking charge in 1328 he immediately dealt with what problems cropped up in Europe (namely, Michael III Shishman of Bulgaria's attack on Adrianople) then prepared to set off with Cantacuzenus to relieve Nicomedia and Nicaea, both under siege. At Pelecanum in 1329, on the road to Nicomedia, the Byzantine army scored some early successes against the Ottoman blockaders but after inconclusive skirmishing began to withdraw; the Ottomans fell upon the Byzantines, but Cantacuzenus managed to ward them off until the army was able to be ferried back across the straits to Europe. Seeing that Byzantine power alone would be unable to smash the new Ottoman dynamo, Andronicus elected to find some allies. The Emirate of Aydin and the Emirate of Saruhan were both persuaded to join the Empire as a counterbalance to the Turks. To bolster his position in the Aegean, Andronicus had the island of Chios seized from the Genoese when its populace revolted.
Stephen III of Serbia, taking advantage of Andronicus' absence in the East, had made an attack on Ochrid; Andronicus had Cantacuzenus drive him off, and then made a pact with his old enemy Shishman of Bulgaria to launch a combined assault on the Serbians. In 1330, though, the Serbians attacked Bulgaria first and killed Shishman in battle. Seeing his enemy's weakness, Andronicus pragmatically patched up relations with the Serbs and struck into Bulgaria, seizing the Greek coastal cities of Mesembria and Anchialus. Now that Bulgaria seemed prostrate, Andronicus thought he had time to turn his attention back to the east, and was pleased to be invited to take part in a Holy League in 1332 with the Knights Hospitaller and Venice against the Turks. However, the Hospitallers and the Venetians wanted to attack Aydin, for Aydin was threatening coastal possessions of the Venetians in Anatolia, and Andronicus wasn't quite prepared to abandon his ally against the Ottomans, especially when the Ottomans had just seized Nicaea following a long siege. Andronicus, however, rated an opportunity to initiate negotiations for church union higher than he rated an alliance with the emir of Aydin, and so acceded to the Holy League charter and made a truce with Orhan in 1333, paying tribute in order to keep the Ottomans out of Nicomedia.
In 1333 the territory of Thessaly was left without a ruler after the inopportune death of its current one; Byzantium and the Despotate of Epirus, under John Orsini, made a mad dash to secure what they could of the prize. Andronicus had the bigger army, and upon arrival there in the autumn smashed Orsini's occupying force and conquered the whole territory, winning a major victory. At the same time, though, Andronicus lost Ochrid to the new Serbian king, Stephen IV Dushan. But Byzantium was able to win big in another area. Andronicus' preoccupation with Thessaly had prevented him from making his contribution to the Holy League, which set sail anyway and destroyed much of the Aydin fleet. The Genoese, now rid of their perpetual tormentors, decided to get revenge for the loss of Chios and attacked Byzantine possessions in the Aegean. And since Andronicus had not participated in the attack on Aydin, he was able to ally with them against the Genoese. Cantacuzenus was dispatched to Anatolia to sign a pact with Umur Bey, the emir, and with Umur's aid the Genoese were smashed and even forced to yield Phocaea, on the Anatolian coast.
In 1337 dynastic troubles in Epirus following the assassination of John Orsini allowed the Byzantines to make book. While the intervention prevented Andronicus from punishing Orhan for violating his treaty and capturing Nicomedia, it did allow Cantacuzenus to crush an Albanian revolt and follow it up with an invasion of Epirus itself, which collapsed and was seized in its entirety. Cantacuzenus was able to consolidate Byzantine rule and smashed an Epirote revolt at Arta in 1339. With this success, the Latin barons of central and southern Greece offered their vassalage to the emperor, so long as they were treated well.
However, there were ominous clouds on the horizon, even after the brilliant seizure of Epirus. The participation in the Holy League had allowed for negotiations with the Western Church for union, but the theological debates that ensued proved unfortunate. At the talks, a monk of Mount Athos, Gregory Palamas, brought up the practice of hesychasm, which was a rite done by his fellow monks that, the monks believed, enabled them to see the light around God Himself. Barlaam of Calabria, another of the Greek delegates, claimed that this was lunacy, and that mysticism was incomparable to philosophical thought in terms of the ability to know God. Theoretically the matter was settled when Barlaam's accusations of heresy were rejected and a gag rule put in place, in 1341. But church union was still proving a tough nut to crack.
In that year, in the month of June, Andronicus III fell sick and died within a few days. He was forty-four years old. Things at the end of his reign seemed bright. He had secured Thessaly and Epirus, even if the last shreds of Byzantine Bithynia had been lost, and possessions were retained and even expanded in the Aegean. Best of all, his general Cantacuzenus was still alive and well, the main architect of his success, and surely he would become regent for Andronicus' young son John V.
The Beginnings of Civil War
John Cantacuzenus had been named by Andronicus as a regent for his as-yet unborn son in 1330, when Andronicus had been extremely sick and fearful of death. He expected to be awarded this position in the summer of 1341, with good reason. Cantacuzenus already had command of much of the bureaucracy, and things largely kept humming as they usually did, but made certain to refrain from having the Patriarch crown him coemperor, as the grand duke [2] Alexius Apocaucus advised.
The death of Andronicus, who had been perceived as a strong emperor during his thirteen years on the throne, set off threats from the neighboring powers. Stephen Dushan renewed his attack on Byzantine Macedonia, another Albanian revolt erupted, John Alexander of Bulgaria threatened to take revenge for the loss of Mesembria and Anchialus, and Turkish pirates attacked the Thracian coast. In addition, the Latin barons had to be accommodated to make bank in Greece, and Cantacuzenus had in his possession a candidate for the throne of the Empire of Trebizond, a Greek state in northern Anatolia, whom he wanted to use to exert political influence there. As Cantacuzenus prepared to take on all of these problems, he quickly convened a synod on Palamism, the debate over hesychasm, and had Palamas' main opponent Gregory Acindynus condemned. He then broke up the pirate attacks and intimidated the Bulgarians and Serbs into making peace, and accepted the submission of the Latins. It was an excellent start.
His power was soon forgotten by his enemies in the capital. Alexius Apocaucus, the empress-mother Anna, and the Patriarch, John Calecas, were all plotting to take control of the regency. Apocaucus, however, made too much noise, and Cantacuzenus came back to Constantinople in August and had him imprisoned. On the empress' request, though, Apocaucus was released. Cantacuzenus was apparently unaware of her complicity, and anxious to have an ally in the city. Next month he started off towards southern Greece to formally impose Greek administrators on the Peloponnese and install detachments from the Byzantine army. In his absence, things got much worse.
Cantacuzenus had the misfortune to be one of the largest landowners in the Byzantine state. His family estates, mostly around Didymotichus in Thrace, aroused a great deal of envy. In addition, they were symbolic of the creeping gains that the landowning elites had made since the days of relative meritocracy during the Macedonian dynasty centuries before. Cantacuzenus and his fellow magnates were facing constant opposition by merchants and tradesmen. Apocaucus elected to make use of this factor in support of his rival regency. He allied with the Patriarch and the empress-mother Anna, and led mobs in ransacking Cantacuzenus' house in the capital. Anna then fired Cantacuzenus from his job as grand domestic. The general, understandably enraged but with his army still in Thrace, had himself declared co-emperor and gave up on the Peloponnese.
John VI, Cantacuzenus, had the main army, but his opponents in the Regency held the capital, and they had a significant symbolic advantage in actually controlling the person of the rightful emperor, John V. Cantacuzenus was abandoned by some of his natural allies, the big magnates, because of these strikes against him. At the same time, Apocaucus did his best to incite the urban poor to rise up against landowners who supported the pretender. When John VI left Didymotichus to seize Adrianople, first city of Thrace, he managed to convince some of the burghers and main municipal officials to declare for his side. But Apocaucus had the patriarch excommunicate Cantacuzenus and sent his son Manuel to incite an urban riot and drive out the burghers, denying the pretender his prize. Manuel was made governor of the city, and fortified it well enough to prevent John VI from successfully capturing it. As a wave of urban violence swept across Thrace, Cantacuzenist city councils were imprisoned or driven out, and Cantacuzenist garrisons were expelled and slaughtered. All John VI had the ability to do that autumn was prevent John Alexander of Bulgaria from capturing Adrianople, somewhat altruistically, but he himself could do no better. By the end of the year 1341, John VI was left with only a slice of the Thracian countryside, as the Regency commanded the loyalty of most of the cities. Thessaly and Epirus, which had been conquered by Cantacuzenus himself not so long ago, refused to declare a side.
In 1342 Cantacuzenus smelt an opportunity: the governor of Thessalonica promised to give his city up despite having publicly declared for the Regents. All John VI needed to do was appear at the city walls with an army. The pretender lost no time, and brought the bulk of his army down the Hebrus valley to the city, but even at his fastest pace was unable to get there fast enough. The Thessalonican mob heard rumors of his approach and of the governor's infidelity, and led by Apocaucus' other son John they overthrew the governor. They called their city government the 'Zealots' and promptly set about slaughtering any magnates within the walls. John VI was met with an implacable, popularly motivated resistance upon his arrival beneath the walls of Thessalonica, and was forced to withdraw. He met another diplomatic defeat when Michael Comnenus, his candidate at Trebizond, was expelled in favor of John III Comnenus, who was a partisan of Apocaucus and the Regency.
The War Widens
That summer, John VI elected to seek help from the only remaining place he saw it: Stephen Dushan of Serbia. At a personal meeting in southern Serbia, Dushan set his own terms. He would aid John VI in claiming his proper place on the throne, in exchange for the ability to keep any conquests he made from the Regents. John VI, too, had unleashed a dangerous force, but he felt he had no choice, met with insuperable resistance at every turn. The summer did not end well for the pretender, for his initial assault on the Regency fortress of Serres met with failure due to an outbreak of dysentery in his camp, and he was forced to pull back to Serbia. Stephen Dushan, on the other hand, gleefully seized Castoria and Edessa with little trouble.
Cantacuzenus finally managed a major success in the autumn of 1342, when Thessaly, long on the fence, came over to his side and accepted his governor. Not a small part was played in the decision by the approach of Stephen Dushan. The Greek Thessalians wished to avoid the reimposition of foreign rule and so the scales were tipped to Cantacuzenus. Temporarily blocked off from his ambitions, Dushan retired for the winter. At the same time, Cantacuzenus' wife, Irene, was able to hold out at isolated Didymotichus, aided by a rogues' gallery of allies: John Alexander of Bulgaria, who wished to keep the civil war going as long as possible, and Umur Bey of Aydin, loyal to his old friend Cantacuzenus, who sailed a fleet up the Hebrus before winter's onset forced him to return to Anatolia.
The Regency's hold on the western Empire totally collapsed in early 1343, when Cantacuzenists seized control of the Epirote government and received troops from the pretender, and Albania was conquered by Dushan. The threat of Serbian dominion was enough to push the key city of Beroea into Cantacuzenist hands, too. Things were looking up as John VI brought an army together to besiege Thessalonica. But his success invited opposition. Stephen Dushan was not satisfied with his Albanian and Macedonian gains, and further ones could only be made at John VI's expense. He abruptly switched sides, timed with the arrival of Alexius Apocaucus with a relieving army at Thessalonica. Met with these twin attacks, Cantacuzenus retired into his new Thessalian stronghold and sent for help from Umur Bey. Leaving his son Manuel Cantacuzenus in charge at Beroea, he set off with Turkish troops to relieve his wife at Didymotichus. In early summer, he finally succeeded, and Irene Cantacuzena's exhausted supporters were finally allowed rest. Umur Bey sent his troops to plunder the Regency-controlled parts of the Thracian countryside as his Cantacuzenist allies caught their breath.
To gain extra support, the Regents decided to take a theological approach. The Empress-mother Anna pawned the crown jewels to Venice, and tried to get the Venetians to resurrect the Holy League to renew attacks on Aydin. She also took the opportunity to imprison Gregory Palamas and declare for his opponents, for the sake of getting credit with the Western Church. Anna also personally submitted to papal authority. This, and the departure of Umur's troops, allowed the Regents a good shot at smashing the Cantacuzenist forces in 1344. Bulgaria and Serbia joined Apocaucus for a multipronged strike at the pretender. John VI brilliantly repelled the Serbians with the remainder of his Turks from Aydin. He then linked up with Manuel at Beroea and smashed Alexius Apocaucus' army, aided by the failure of John Alexander to come to his allies' aid. The Bulgarians had contented themselves with occupying Philippopolis, and thus didn't figure into Cantacuzenus' calculations at all. John Alexander did not oppose the pretender as his army marched into eastern Thrace. Rats began to flee the sinking Regency ship; even Apocaucus' son Manuel, putative governor of Adrianople, fled his city for the Cantacuzenist camp.
Cantacuzenus took two minor hits in the fall of 1344. One was the decisive defeat of Umur Bey's forces in Aydin. The Venetians smashed his fleet and captured Smyrna, even with the reinforcements that Umur had brought from Europe. The second was Manuel Apocaucus' failure to bring over Adrianople. Zealot mobs had seized control of the city, and when Cantacuzenus drew up his army underneath its walls, it was rebuffed. John VI sat down to a siege over the winter. At least now he was strong enough to fight without Turkish reinforcements. As he blockaded Adrianople, Anna and the Regents began to purge the capital of suspected Cantacuzenist collaborators, excommunicating the jailed Gregory Palamas and inciting mobs that attacked theological and class enemies.
The Cantacuzenist Victory
In 1345, Cantacuzenus was joined by two allies: Umur Bey of Aydin, who had managed a brilliant trap in the Smyrna harbor and captured much of the Holy League fleet, and the Ottomans of Orhan, who figured out which of the two Byzantine sides liked Turks better. Adrianople surrendered even before the Turks got there, and the Zealots were duly purged. With Ottoman reinforcements, John VI was even able to march to the Black Sea coast, tightening the noose around the capital. He prepared to march on Serres, a Regency city besieged by the Serbs, to relieve it and perhaps convince the city council to switch to his side. News of Alexius Apocaucus' death, lynched while stupidly hanging out with his aristocratic prisoners, induced him to abandon the Serres drive and make for Constantinople. He failed to capture it, for John Calecas and Anna had things well in hand. He also was unable to secure Thessalonica despite the defection of its governor, John Apocaucus. Apocaucus' betrayal got him the enmity of the Zealots, who had him murdered and who then assumed control of the city. Still, the two remaining Regents were confined to the capital and Thessalonica now. The war was clearly entering its endgame.
But that did not mean that the other participants were finished fighting over the spoils. Stephen Dushan seized control of Serres and then marched straight down to the Aegean coast, conquering the Chalcidice and Mount Athos. The Byzantine Empire was cut in two. To celebrate, Dushan crowned himself emperor in 1346, and John Alexander elevated himself to the same rank so as not to be outdone. Cantacuzenus, learning of the new titles, was spurred to secure his own crown. At Adrianople, the exiled Patriarch of Jerusalem officially made him John VI, though only as co-emperor with John V. John VI also held a council at Adrianople that reaffirmed support for Palamism and deposed John Calecas at Jerusalem. The Regency tried a last few blows, hiring Turks from Saruhan, but they deserted to Cantacuzenus after a short period of pillaging. Anna also lost Chios and Phocaea to the Genoese, who were anxious to make some progress since they had failed against Umur Bey.
John Calecas was proving to be one of the final impediments to the end of the war, so Anna had him deposed in February 1347, then opened negotiations with John VI. He promptly infiltrated a thousand of his men, with himself at their head, into Constantinople to make the negotiations go more smoothly. Anna agreed to a power-sharing arrangement, whereby John VI would be senior emperor until John V came of age, solidifying the whole thing by marrying John V to Helena Cantacuzena, John VI's daughter. John VI also married off another daughter, Theodora, to Orhan, confirming that alliance as well. All land, too, was to be returned to its original owners (within what was left of the empire). John VI had finally managed his victory after more than five years.
The victory seemed hollow, though. Stephen Dushan was so far the biggest winner, having conquered copious border regions and split the empire in twain. John Alexander had had modest gains, capturing Philippopolis. Genoa had also regained all she had lost to Andronicus III. Thrace was in ruins, from both Turkish depredations and social warfare. There was practically no money left in the treasury. And the Zealots still retained Thessalonica. But there still was some brightness left. Epirus and Thessaly, the great conquests of Andronicus III and Cantacuzenus, were still under Byzantine control. John VI now had an excellently trained army, and he himself was a solid professional leader, ready to win back territory from the Serbs and Bulgarians. Dushan's gains were many, but his means were few. Byzantium still had a chance.
The Renewal of the Civil War
What ruined that chance was the Black Death. Cantacuzenus had been crowned, and was busily threatening Stephen Dushan with war unless he returned Beroea and Serres, which would thus reunite the Empire, when the plague arrived in the spring of 1347. Dushan had been equivocating, attempting to hold off fighting for as long as he could, sure that he would be unable to hold what he had seized; he was gratified by the abrupt prostration of his great enemy and immediately began a drive on Epirus. John VI, suddenly bereft of his trained army and his tax revenues truncated by the demographic disaster the Byzantine Empire was undergoing, desperately applied to help from all of his allies. The Turks were the only ones that sent any aid at all, namely ten thousand men from Orhan, but they only made things worse, failing to march against the Serbs at all and instead pillaging Thrace (again) and then returning to Asia without having fought at all. Umur died in 1348 before his own expedition was able to set sail, wounded in a battle with the Holy League.
Cantacuzenus indomitably struggled on, lowering customs duties to lure traders away from Galata, the Genoese trading colony, and amassing an army and a navy that strained his fiscal resources to the breaking point. Genoa could hardly be expected to simply allow commercial warfare with impunity, though, and promptly burned Cantacuzenus' small fleet at anchor and attacked what merchantmen were in the harbors at Constantinople to intimidate them. John VI grimly defeated what Ottoman troops were left in Thrace and besieged Galata by land. His second fleet was destroyed in battle with the Genoese, but the third was a menace they could not ignore, and if only to allow business to resume the Genoese ended the war, offering a lump sum, a ten year lease on Chios and its eventual cession to the Empire. John VI captured Phocaea for good measure. Cantacuzenist supporters also came out on top in Trebizond, and when the Serbians approached Thessalonica in 1350 after having overrun Epirus and Thessaly, the Zealots finally ended their class-warfare opposition to Cantacuzenus and asked for help. A two-pronged attack, with the emperors moving by sea and Matthew Cantacuzenus, the emperor's son, moving by land, succeeded, and inconclusive skirmishing resulted in eastern Macedonia before Dushan and Cantacuzenus agreed to a peace of mutual exhaustion.
Even this was not the end of John VI's troubles. He had set Manuel up as a ruler in the Peloponnese, accepting the suzerainty of a few of the complaint Latin barons (the rest had reneged) and gave Matthew extraordinary powers over Thrace. But in 1352 John V attacked Matthew Cantacuzenus, and threatened to renew the Zealotic class warfare. Matthew was forced back to the citadel, and only saved when his father brought in more Turks to relieve the city. A second civil war began, this time with John V fighting on his own behalf. John V was able to coax Dushan and John Alexander to send him troops and got a loan from the Venetians. Cantacuzenus called on Orhan and received more men. The two armies clashed on the Hebrus River in 1352, where John VI's tactical acumen resulted in a crushing Cantacuzenist victory. John V fled first to Tenedos, then to Thessalonica, where he was able to hold out with his mother. Now more troubles damaged the Cantacuzenist cause. Attempting to have Matthew crowned in place of John V, John VI was unable to find compliant clergy, and was at the same time unable to reduce Thessalonica. His Turks began to rampage out of control in Thrace, and amassed significant pillage; in desperation, John VI offered them ten thousand hyperpyra [3] to leave Europe. An unlucky earthquake knocked down the walls of nearby Callipolis while the Turks were considering the offer, and with Sulayman at their head they occupied the town and refused to yield it to John VI. Orhan failed to respond to Cantacuzenus' desperate missives to give up the town in exchange for the gold. The Turks, who had seized all Anatolia, were now in possession of European territory.
John V made his move then, sailing to the capital and inciting one last urban revolt. John VI, confronted with an out of control uprising, agreed to reinstate John V and abandon the cause of his son. Less than two weeks passed before he abdicated the throne himself to become a monk. The civil wars were finally over.
What Was Left of Byzantium
Evaluating the social impact of the great civil war must be done with care. The urban poor themselves had little beef with the Cantacuzenist magnates. If the nobles oppressed anybody - well, when they oppressed anybody - it was on their own estates, not in the cities. The urban poor sided with the people who did oppress them, with the merchants and tradesmen and bureaucrats. This was no simple squabble of rich and poor. But there was a significant social element in the fighting, for in many ways the civil war was an outgrowth of the old, hundreds of years old conflict between the middle classes and the landowners. The meritocratic system that obtained in the later Macedonian dynasty, especially under Basil II, was no longer in evidence. The Comneni had actually increased the power of the magnates by the system of military pronoia grants that they had imposed in the eleventh and twelfth centuries, and the system continued to work to the landlords' favor in the fourteenth. Generally, the aristocracy could rely on the aid of the monks, the anti-Westerners, and the Palamites, whose monasteries received a great deal of money from aristocratic grants. Since Italians were necessary for trade, foreigners sided with the regency and the middle classes, as well as the anti-Palamites. But even then, more immediate concerns could overturn those loyalties, and things were not always that clear cut on the ground.
John VI's short reign and his civil wars were the beginning of the end. First the destructive conflict that laid the Empire bare to the ravages of its neighbors, then the plague that prevented a response, and finally the renewal of the civil war prostrated the state and left it without much hope. What had been feared for nearly three centuries had come to pass, too, and the Turks had finally circumvented the Straits and placed themselves in control of a gateway into Europe. They had done so invited by a Byzantine Emperor and paid at his behest. But despite the calamity that befell the Byzantine state during his time, Cantacuzenus was not a bad emperor. He showed skill during the first and second civil war, and weathered many calamities, including the devastation of the Black Death. But without the revenues he had been able to obtain before the plague, or his army, he could not repel all of his enemies or keep his Turks on a leash.
Footnotes
[1] = megas domestikos = commander of the army.
[2] = megas doux = commander of the navy.
[3] = the gold currency of the Byzantine Empire.
Sources
John VI Cantacuzenus' History is one of the main sources for this period. He provides a fine narrative for the civil war from his own perspective, though one must of course be careful of bias.
Nicephorus Gregoras' Roman History also covers this period, though in far less detail, and can be used to correct Cantacuzenus when he tends to glorify his own actions.
Nicol, Last Centuries of Byzantium extends the Treadgold narrative and has recently been revised with aid from modern scholarship. On the Civil War itself it is nigh invaluable.
Treadgold, A History of the Byzantine State and Society was fantastic for these purposes. It's a very good and in depth study of the Empire as a whole, using modern scholarship instead of the older, Gibbonesque studies that obtained previously, and its incisiveness does not diminish as it moves beyond the apogee of Byzantine power. Excellent book.
Your knowledge of that time and place, as I said before, is amazing. 
