Did the fact that Christians from Western Europe looted Constantinople in 1200 play a role in the Eastern Roman Empire's decision to stop identifying themselves as part of the Catholic Church, or were there already deep theological and political divides?
The pope who sent the schism message delegation died before it reached Constantinople. And the patriarch of Constantinople at the time, also died before his reply made it back to Rome.
> a role in the Eastern Roman Empire's decision to stop identifying themselves as part of the Catholic Church
From their point of view, the West abandoned the true (i.e. orthodox) faith.
Also, it's hard to argue that the Eastern Christians changed more than Western ones. For example, since the 12th century the pope has forbidden priest marriage. There is some debate in the Catholic Church about allowing this again. If that is implemented, it would simply be a reversion to what the Orthodox Church has always done.
Catholic means universal, so both present themselves as the original and true church, with the head either in Rome or Constantinople/Pentarchy. The actual break of communion comes from 1054 but really began much earlier.
Even in protestant churches like the Presbyterians and the Methodists you will hear references to the "Catholic Church" where it refers to the universal church that is inclusive all all believers regardless of denomination. For example in shows up in the Nicene Creed and the Apostles Creed.
Both churches have always identified themselves as "Catholic", or universal in the Greek language (katholikos). Orthodox Churches still use the creed in every service, where they say "We believe in one holy catholic and apostolic church".
Also, it's not like the Roman Catholics claim to be heterodox or something, they also claim that their faith is "orthodox".
In the 1180s the Empire was governed by a French princess (regent for her son) and her late husband was very pro-western/latin. The relations between the Catholic crusader states and the Byzantine empire were also very good and Italian merchants controlled most of its economy.
Then.. an anti-western emperor came to power had all the Latins/Italians in Constantinople massacred (>10% of the population) and things went pretty much downhill from there. It was very rapid, though. There were of course disagreements before the late 12th century but both sides generally acknowledged that they were part of the same Christian word/universal empire (even if they didn't quite agree who was in charge).
1054, in fact, but the 1204 ransacking of Constantinople certainly didn't help with how the "Franks" (because that's how the Catholics were mostly called) were seen by the Christian-Orthodox (if it matters I'm a Christian-Orthodox myself).
I was reading a travelogue written by a Russian monk (? not sure, either a monk or a wealthy boyar predisposed to the Holy stuff) who was visiting Constantinople sometimes in the early 1300s, so a century after the whole tragedy, and he was still describing how destroyed the city looked because of the Franks and what big of a tragedy that was.
If you read Wikipedia, there was the Massacre of the "Latins" in Constantinople in 1182. That almost certainly made it easy to make it a revenge play for the Venetians and associates.
What I find most interesting is the Romans were unbeatable in battle, even the Byzantines. However, maintaining a large military presence was expensive and politically difficult to manage. So they used annual mercenaries from the north for the usual frontier squabbles, and the main army did the heavy lifting. It fell apart when there was a major conflict, and didn't help that the army held the city hostage demanding more money. So everyone was corrupt it would seem. Also there were the persistence of rumors of knights that may have kept most of the treasure for themselves and headed off to Cyprus. The Knights Templar were insanely wealthy given the times and cost of resources to mount expeditions.
They were, though? Adrianople, Yarmoud, Manzikert, Myriokephalon etc. it's just that the empire was extremely resilient and was generally able to recover from disasters which would have led to the collapse of most other states.
I think Hannibal is owed some credit for marching elephants over the alps - I believe Rome razed and erased Carthage on their 3rd or 4th try? No matter really, it wasn't their 1st.
By 1200 the Romans had been beaten in battle many times. Their loss at Manzikert to the Turks in 1071 severely weakened the empire, and they never really recovered from it.
It's funny how the Battle of Manzikert went from being an obscure battle only a handful of scholars cared about to a major topic in popular consciousness.
It's actually not quite so clear cut. 1053/1054 was when mutual excommunications between Rome and Constantinople happened, but (as the schism itself is evidence of) Constantinople did not speak for the entire church, and other eastern sees continued communion with Rome for quite some time afterward.
It really wasn't obvious at the time, though and it took at least 100 years or more for the split to become permanent.
e.g. There is currently a schism between the Orthodox Church and the Russian Orthodox Church which technically is not that different. Does that mean that the Russian Church is no longer Orthodox?