Without doubt, Jews started the Church -- the Book of Acts describes some of the first organizational meetings of what was to become the Church. But was it what we call the Catholic Church today? Western Catholics claim that the Church of Rome is the direct successor of the Church of the Book of Acts, with the apostle Peter as its founder, while the Eastern Orthodox Churches are factions that broke from this original lineage. It may be more proper to say that what we now call the Catholic Church is just one faction of a church that was only strongly centralized after it became the state church of the Roman Empire and that, before that, was sufficiently diffuse that it is hard to describe it as a unified entity the way we now think of Catholocism.