No, Croats are very Catholic. Serbs are Orthodox Christian. There's rivalry between those religions in the Balkans.
In Bosnia you had the Muslims (Bosniaks), Catholic Croats, and Orthodox Serbs, so there it was members of 3 major religions clashing. The Jews and others stayed out of it and some had to escape to safety.
Thanks for straightening me out on that. A very difficult
area to understand and, I would think, not a nice place to be.