the person who founded the Catholic Church would be Contantine the Great, who may have been uncertain about one G-d, but was pretty darned sure about One Empire and One Emperor.
No Sir....
Christ said to Peter... Upon this rock you should shall build my church! What church do you think that was? All the other Christian were not around at that time so that leaves only 1.
Christ conformed Peter as the first Pope of the Catholic Church and there has been a Pope ever since that time...
Its right there in the Bible for all to read...