There are at least four kinds of Ukrainians. Russians with Ukrainian citizenship (a lot of these in Crimea and L/DNR), Russian-speaking Ukrainians, Ukrainian-speaking Ukrainians and Western Ukrainians, who did not live in the Russian Empire or Soviet Ukraine before 1944, and have Roman Catholic-controlled faith based on Orthdox rituals.

The first three groups form a continuity and is not perfectly correlated with loyalty to Ukrainian state.

Plus hungarians and some tatars.

Caveat emptor: I'm not from Ukraine.