Dear Vrylakas!
You began some very interesting & speculative issue of Russian History. I tried to answer on it partially in tread
Best General EVER? page 6 - about Ghenghis Khan story, but I can repeat it.
First thing is first: Novgorod won - firstly, but lost later..
All first Russians Princes "who began Russian History":
Rjurik (Erich), Oleg the Seer (Helgi), Igor (Ingvar), Olga the Saint (Helgi) - were Vikings by their names, customs, military traditions & common Law usage. When Toynbee tell us, that "beginning of Russian culture was pure Scandinavian" he knew & understood this issue pretty well. (If anybody tried to check Olga method of quelching Drevlians mutiny, he found that Pnincess used very common way & practice of Swedish & Denmark princes of that period.)
First "pure-Russian" Prince who preferred "local" customs & tradition was Prince Svyatoslav Igorevitch. Sad Irony of this statement is - Sviatoslav Igorevitch used not Slavonic, but Pechenegs - i.e. Indo-Iran by nature - customs & tradition. Slavonic leaders never used (till Sviatoslav) public declamation before their forces before battles, or send any offensive letters to enemy rulers, but this was usual military practice of Pecheneg leader. (We've got detail description of Sviatoslav & his clothes - it is description of "steppes warrior" not inhabitant of grassland river valleys that more appropriate for East Slavonic customs.
It seems, that influence "steppe" or Iranic culture was strongly superior in Russia of that times, then any Western or "pure Slavonic" culture influence. (It seems that aggresive international policy of Sviatoslav & need in Pecheneg cavalry as mercenary support was reason.) In any case - Bulgarian leaders (whose culture had the same Indo-Iranic roots) found Sviatoslav their "blood leader", but the same Bulgars never considered Slavonic inhabitants of Balkans as their "brothers"!

We got really many signs of heavy Bulgar (or Pecheneg, or Indo-Iran) culture influence in Kiev culture in Sviatoslav & his elder sons rulership, but his youngest son - Vladimir the Saint was teached by Viking military leader Sveneld & fall under strong Scandinavian influence. If you check war between Vladimir & his brothers, you will find that Vladimir as head of Novgorod military forces enter Kiev region & met strong military resistance from ALL local inhabitants who name him as USURPER. If you check names of Vladimir' comrades you will find that more the 4/5 of them had pure Scandinavian names, but names of Vladimir rivals were "pure Slavonic". Then we can make decision that Vladimir' attack was aggression of the same sort as aggression of Rurick against former slavonic princes Askold & Dir who were killed by Rurick in process. (Interesting thing - Slavonic leaders Ascold & Dir were never acknowledged as "Russian" leaders, when Rurick was - "Russian". Reason is - Rus is ancient name for Neman River. "Russland" is ancient region that have modern Liethuanian name - Jemaitia, from Baltic "Jamos" - "Low". In some sense former "Russland" is named today as "Niederland"

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In any case - Vladimir victory found strong support in Byzantium. Byzanthim preferred any prince in Kiev with some respect to the Law - to any "steppe" leader of Bulgarian origin. (It was times when Bulgarians were considered as strictly "bad guys" of Europe. They had so bad reputation that they were blamed in complete outlaw treats in politic till... Modern word "bugger" is derivative from "Bulgar" & Bulgars were blamed for this practice as well.) In any case most strong state of this region - Byzanthium preferred "Viking Prince" as Russian leader to any "bugger" in his place

. Then Novgorod won.
It seems for this acknowledging of his Power as Great Prince of Kiev (instead of bitter resistance of local Slavonic population to Viking oppressors) Vladimir brought Orthodox Church in Russia (& Byzanthium Priests & Military Advisors as extra). Russia had got her Chrtistianization.
Most subtle thing in this process was - most Vladimir supporters were Viking Pagans & Novgorod was considered as main source of Paganism. Then Vladimir exiled most part of his Viking forces & "Christianised Novgorod by Fire & Sword". But...
Vladimir was usurper from common russian point of view (he was son of some "murom-slaverin". Murom was region of Finnis-Ungarian tribes, then most loyal supporters of Vladimir became north-east tribesmen of Finno-Ungarian origin with their famous Leader - Ilya Muromets (idealistic figure of "Russian Bogatyr") who was brother of Vladimir mother. From that time we got really weird picture - when strong Orthodoxy supporters were people of Finnish-Ungarian blood (from north-east of country), Pagans were - Slavonic majority (central part of country with west-south west) , Muslims had their Bulgarian (Indo-Iran) (East-south-east & south) roots & north-West region with strong Viking-Baltic influence had... strong inclination to Catholicism.
This was "powder barrel" situation - Vladimir death became spark to this powder barrel"!
Most important thing in this period were - personalities ov Vladimir heirs. This Prince tried to make as many alliances as possible & "had hundred wives". Each & every of these wives brought heirs for Vladimir & all of them became leaders of their compatriots. All, with one notable exception - Finnish-Ungarian tribes never had their Princes then Vladimir never seek any alliances with them.
It means that main part of Vladimir army of Orthodox Faith (& very warm & friendly relation with Byzantium), Finno-Ungarish origin with their Leader Ilya Murometz (he outlived his nephew) didn't have "their Heir" at all! They just abstain from any later bloodshading waiting for Victor, sworing their allegiance "to any winner, because our Honour is with any son of Vladimir blood".
This position had two major consequence - Byzantium from that momemt & ever bind her loyalty with North-East Russia Leaders, because saw them as "loyal supporters of any lawful deeds" & "most zealous supporters of Orthodox church" - this attitude of Byzantium never wavered to North-East political Leaders & they never lost their Orthodox beliefs due to fact that Christianization of Russia brought them to Power. This strong Link between Byzantium, Orthodoxy, North-East lands (modern Motherland for Russians) & local tribes of Finnish-Ungarian origin never dissolved in History... (If you check modern "folk" clothes of "Russian folk ensembles" - for Example "Beriozka" or Moiseev troup - you will see "kokoshniks", "spear-looking beads" on the girls & many other interesting things that you never find in any "Slavonic folk ensemble" of Europe, except... - "Finnish folk" & "Hungarian folk" troups! All these things are "trademarks" of "Finnish-Ungarian" culture & strong "birthspots" of Russian (or Great Russian) Culture in comparison with Ukrainian, Byelorussian, Serbian or Polish cultures. In some sense modern Russian (Great Russian) culture doesn't equal to former Russian (East Slavonic) Culture of Great Principality of Kiev times. (When you would realize that strong Orthodoxy is most feature merit of North-East Russia (modern Russia) from XI century, but other Russian lands (modern Ukraine & Byelorussia) remained as at most "pagan" countries till XIV century you will understand all "Uniates" stories about Ukraine - better

. (Then I used to name Russian (Great Russian) as "harsh Orthodoxy" & used to comparise it only with "Zealous Catholicism" of Poland. There are things of one range, but "Uniated" Church of Ukrainians or "Catholic"/"Orthodox" Church of Byelorussians is "soft" in my language & belong to complete different things. It's resembles Magnet of some sort - you've got North Pole of Magnet, you've got South Pole of it - & some "grey zone" between

. )
But - let's return to our topic. In really big variety of possible heirs of Vladimir there was one notable exception - grandson of Danish King Canute the Great - Jaroslav (the Wise). Why this exception was notable? Byzanthium had her grudge to any non-Christian sons of Vladimir & descendants of Christian kings with bad relationships with Byzanthium. Then heirs of Magyar, Bohemian, Polish & any other blood were dismissed. But Vikings (Normans) of that times were - different fish. They fought Catholics in South Italy, made "Varangian Guards" of Byzanthium Vasilevs" & recommend themselves good in fighting against Muslims. Then Byzanthium envoy nudged Ilya Muromets & Ilya' military force to help Jaroslav cause.
Just imagine this story: Jaroslav got helping from Danish Vikings of his granddad, Byzantium support & Finnish-Ungarian military forces of his father. His rivals were: Slavonic majority with helping of Bulgarian & Magyar nomad leaders, but - "God used be on side of grand batallions". Jaroslav armies went through Slavonic resistance as knife through butter! (Of course - all his rulership times was permanent subduing of local uprising against "occupants" ot three sorts around!) But we must state - Novgorod (as operational base of Danish forces of Jaroslav) won again!
Then - most interesting thing occured - Jaroslav was considered in Europe as grandson of Canute the Great & took in account as "Danish Prince". (Don't forget that one of his daughters became Queen of France, other - Queen of Hungary & famous Hasting of Hardrad (killed by Wilhel the Conqueror) was Jaroslav nephew. It created European belief of very high "European influence" of Russian affairs. Bringing of "Jaroslav Truth" (Law codex of Russia if that times) which was "Canute Truth" in disguise helped to this misunerstanding.
But grim truth was - Jaroslav was considered by Slavonic majority of Russia as "Viking usurper" & his Power was Military Power of his Army. & Jaroslav Military was in its core - not Viking (Danish) by blood, but Finnish-Ungarian. Another very important issue - Byzanthium attitude. Byzanthium reaction to fast intermixing in international Policy of Jaroslav with Europe (Catholic Europe!) was really bitter! If you check Russian Chronicles you will find that Byzanthium envoy from some moment began named as "trouble-maker" for Jaroslav gang, but still remaned praised from Russian military leaders as "Defender of Faith". You find some specific "cries" in Chronicles that blame Jaroslav crowd in "bad attitude" to "small peasants of Novgorod" by Finnish origin (you must keep in mind that Jarosolav considered modern Finland as Novgorodian lands & tried to conquer them with helping of Danish Knights, but russian military of finnish origin began (surprise, surprise!) blaming him for atrocities!).
It was time - when Novgorod became considering by Russian military as "evil city" & all Novgorod' inhabitants as "pagans", "schismatics" (i.e. Catholics from Orthodox point of view) & "hateful mutineers". It seems that Byzanthium envoys fed this attitude in North-East lands with great vigour.
Main (& grim) step in this direction became so-named "Vseslav war" when Russian military began fighting with army of Polotsk Principality - it was first time in Russian History when "Enemy" & "Catholics" became the same term. "Most foul deeds" of this war (from Great Russian point of view) became help to Polotsk from Novgorod & Danish officers of former Jaroslav Army. There were first "cleansing" of army ranks that finished in dividing of Russian Army of many warring factions that became main reason of Lubech Sobor that strenghten situation when "every Prince keep his own Province". I'm sure - that was "Death sentence" for Novgorod....
Reasoning is simple. Russia was considered by medieval politics as "Way from Varangians to Greeks". Try to realize simple fact - "Greeks" & "mid-part" of this way were "thicker then thieves" in their Orthodoxy ways. Yep, they must keep Kiev region by brute military forces, but - north part of this way was in Novgorod lands & Novgorod himself. Then - Byzanthium & North-East Russian leaders must overcome Novgorodian independence by force of - took very sever trade losses. Until Novgorod population had some support from the West - they kept some illusions, but after Willem the Conqueror killed Harold the Hardrad in Hasting field & Pope Innocent excommunicate Emperor Henrich (Jaroslav' son-in-law) - any help to Novgorod was considered in Europe as foghting against England, Normandy & Pope himself! Normandy & Bullion was start points for First Crusade - then anybody tried to help Novgorod was considered in Europe as "Jews" & "Muslims" simultaneously!
Try to get in "Jew" & "Muslim" skin in medieval Europe & you will see Novgorod' problems! By the way be aware about this half-naked big guy with red hood with eyes slits red leather apron - why he took this big torch & moves in your direction? Maybe he want to burn out your shackles - manacles, eh?

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Well, when Knights input from West dried completely, but input of Byzanthium Knights into Russian lands only grew - days on Novgorod were counted...
Novgorod was totally crippled in 40-s of XIII century after three big "cleansing" of this wretched " broken city by Alexander Nevsky forces. (Nevsky outlived Tartar invasion due to fact that his father was blood-relatives of Jebe & Alexander married all three younger sons on Ghenghis Khan grand & grand-granddaughters, executing his elder son Vasily (who opposed Mongol invasion) in process. From this moment Great Russian Princes of Vladimir (& Great Princes of Moscow later) began regularly "cleanses" of Novgorod on reason of "non-strict Orthodoxy of its inhabitants" till Ivan the Terrible invasion. When you would realize that "Russian military forces" consisted Tartar Cavalry because "Great Princes of Moscow" became "Ghenghis blood" you will understand - Novgorod hadn't any chance against cooperative onslaught from "Golden Horde" & "Muskovy". But they couldn't stop these "cleansings" due to trade importance of Novgorod...
It weren't only confessional or ethnic problem of Novgorod' decline, there were economical reasons as well...
"Who gains?" - was main question of Rome criminal Jurisprudency. Answer is - Every Big Power of Medieval times gained from these "cleansing" - Byzanthium had Confessional gains, Great Russia - Ethnic, Tartars - strenghtening of their allies in West (they depend from Russian infantry in civil fighting in Mid Asia), European - all-European solidarity in Crusades - & everybody their economical gains. "Way from Varangian to Greeks" must be profitable, then everybody who control 2/3 of this way was preferably to anybody then 1/3 holder

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Sincerely yours, Alex.