TheLastOne36 said:
In the modern day, following a century and a half of nationalism, the invention of the modern "Ukrainian" identity, Cossack migration and the impact of both Imperial and Soviet Russia, you could rightfully justify their self-identification as a distinct group from Russia, but that is not quite what we are discussing.
You are right that the modern Ukrainian national identity was built largely around the myth of Cossacks - the alleged founders of the Ukrainian state.
The reality was somehow different and original Cossacks would be surprised that someone considers them as "founders" of some nationality.
Kozacy (Zaporozhian Cossacks), were basically outlaws and social drop-outs, who settled in the Wild Fields (sparsely populated area of steppes in the south-eastern part of the Polish-Lithuanian Commonwealth in the borderland area with the Crimean Khanate), became pirates and created their own community and a political-military organization called Sich (also known as Host). Kozacy were neither peasants, nor townsmen, nor nobility, even though members of the Cossack community came from each of these groups. Cossacks were also not people of any nationality or ethnicity. Undoubtedly ethnic Ruthenians were the most numerous group among them, but there were also Poles, Russians, Hungarians, Greeks, Germans, French people, Spaniards, Italians, Jews and Tatars. Kozaczyzna (the Land of Cossacks) was also not a monolith when it comes to religious beliefs, even though Orthodox Christianity dominated there. And ethnic or religious factors were not important for the Cossacks - what united them, was their style of life and their sense of common social affiliation. They lived off what the steppe gave them, as well as off piracy - plundering raids, especially against various towns and villages of the Ottoman Empire and its vassal states. Their own ethos also presented them as defenders of the frontiers Commonwealth against the barbaric Tatars (Crimean Khanate) - they sometimes described themselves as "knights of the steppes". They undoubtedly loved freedom and their riotous lifestyle of a swashbuckler more than enything else. As is presented in the movie "With Fire and Sword", Cossacks did not hate the Polish-Lithuanian Commonwealth. They were eager to fight for their homeland, they wanted to be hired to Polish armies and they frequently were (see: Registery Cossacks, who served as paid soldiers, receiving money for their service, even though it was much smaller than payment of other troops). Apart from Registery Cossacks, also other Cossacks fought as part of Polish-Lithuanian armies in various military campaigns - they were not paid from Polish-Lithuanian State Treasury, but fought under command of their own, Cossack Hetmans. But undoubtedly Cossacks were opposing any attempts of excessive interference in their internal matters by central authorities of the Commonwealth - i.e. they were "a state within a state", remaining loyal to the Commonwealth, but they wanted to be autonomous and out of range of jurisdiction of Polish law. Attempts of subordinating Cossacks to state authorities (as well as to the power of magnates and nobility) and various legal rules were one of the main reasons of the Cossack uprisings in the 17th century. And those attempts in turn were caused by the fact, that Cossacks frequently caused tension between the Polish-Lithuanian Commonwealth and the Ottoman Empire, because Cossacks generally did not want to respect Polish-Turkish ceasefires and peace treaties and continued to raid various Turkish towns along the coast of the Black Sea.
When it comes to Zaporozhian Cossack military power, they fielded both infantry (pikemen and troops armed with firearms), light cavalry, dragoons, artillery and their own fleet, comprising of boats called czajka (plural: czajki), which had crews consisting of 50-70 sailor-soldiers each. The Cossack fleet in various sea battles frequently numbered even 200 - 300 and more boats, they often fought against the Turkish fleet and often were successful in those sea battles. When it comes numerical strength of Zaporozhian Cossacks - they could mobilize up to 120,000 troops, but this included troops recruited from amongst local peasants, who were frequently joining them in their military campaigns. When excluding troops recruited to Cossack armies from peasants, the total number of Cossacks was about 50,000 and of them about 20,000 - 30,000 were "constant Cossacks", who had no other profession apart from piracy, and lived only off piracy.
When it comes to Cossacks serving as part of Polish-Lithuanian armies. They were often present in great numbers, for example:
- in the Khotyn campaign of 1621 against the Ottoman Empire, there were ca. 40,000 Cossacks in the Polish army
- in the war against Russia of 1609 - 1611 in total at least 30,000 Cossacks took part (not all of them at once, though)
- in the campaign against Russia of 1618 around 20,000 Cossacks were in the Polish army
- Polish king Wladyslaw IV wanted to mobilize 100,000 Registery Cossacks for his planned invasion of Turkey in 1648, but he died before doing this*
*Following his death, the Khmelnytsky Uprising started - the straw that broke the camel's back was the cancellation of that planned invasion.
During the Khmelnytsky Uprising, when Cossacks fought against Poland rather than for Poland, they fielded even more troops:
- in the Siege of Lwów in 1648, the joint Cossack-Tatar army numbered 150,000 of them around 115,000 - 120,000 were Cossack troops
The "capital city" of Cossacks was Sich - a large and well-fortified fortress located on one of islands on the Dnieper River.