In any history class about the history of Europe, you would have a hard time not talking about Russia…
Excluding Russia from Europe is a really recent trend actually, it appeared even after the fall of the iron curtain, during the late 90 s, early 2000s as an attempt to marginalize Russia.
Are you going to kick France out of Europe then? Because we've invaded our neighbors way more than Russians ever did. Heck, without the Russians Napoleon would probably have invaded England, achieving complete French domination over the continent!