He annotated a passive-aggressive annotation on a patch I made and basically hijacked a presentation I made because the library I presented did not fit his aesthetics & work style. I don't remember ever acting in an uncivil way toward him.

If you regularly act like an asshole, expect to get a reputation and to be treated like one (even unfairly).

Btw, I'm glad you are bringing civility up. For some reason the lack of a civil vibe (at least from my experience in the Ruby community) really bothers me.