We have Catholic Slavs:
Poland, Slovakia, Czech Republic, Croatia, Slovenia, Sorbs
and we have Orthodox Slavs:
Russia, Belarus, Ukraine, Serbia, Bulgaria, Macedonia
Just to mention that most people in Czech Rep. account themselves as faithless (about 61% by census in 2001, today it’s probably higher number). Czechs aren’t considered to be Catholics, rather Moravians are. But if Catholic/Orthodox is meant as a cultural influence, than yes, Czech Rep. belongs to “the Catholic sheep-fold”.