There is not much doubt now that Ukraine is falling into civil war. Like the English and Scots, Ukrainians and Russians have lived together for centuries. They have intermarried, shared political highs and lows and come to know each other very closely. But that hasn’t meant they’ve liked each other. Only in the area of religion is there any significant difference. The eastern regions of Ukraine are part of the Orthodox world, but as you go west Ukrainians are as likely to belong to the Uniate branch of the Orthodox Church, where their practices and beliefs are conventionally Orthodox, but they pay allegiance not to the Orthodox Patriarch, but to the pope in Rome. Further west again, in the lands ruled by Russia only since the Second World War, many of the inhabitants are Catholics.
This boundary between the Catholic and Orthodox worlds is seen by some historians as the eastern limits of what can be seen as “the West.” Politics in Ukraine has been divided along this east-west line since the country found itself independent after the collapse of the Union of Soviet Socialist Republics in 1991. Where the Baltic states (Estonia, Latvia and Lithuania) were unambiguously western in orientation, and Belarus was just as clearly eastern, Ukraine was big enough to have significant and roughly equal portions of each.
On top of those odd lines of division are more recent enmities left over from the First and especially the Second World War. The Russian-speakers of the east are deeply hostile to the right-wing politics of many of the western Ukrainians. They see them as successors to the Ukrainians who collaborated with Germany in both world wars. And in turn the western Ukrainians see the easterners as backward-looking supporters of despotism and low standards of living. So the antipathies on both sides are deeply rooted and widely held. And religion lies at the heart of the hatreds. It’ll probably take a generation or more before sanity will prevail in Ukraine. That won’t happen until many lives have been lost and/or ruined. That’s the way civil wars work.