Catholicism is a African cult that eventually took over political power from the Roman empire as it collapsed.... it's not Christian and not the "one true church" despite all it's wild claims.Not anymore, but the times of the crusades bear testament otherwise. I would also like to point out how the vatican happens to still exist as a psuedo independent city-state with a very separate religious-political control system. And lastly how the christian faith is actually quite splintered with different variety, catholic, dutch reformed, methodist, etc. There is an entire separate grouping that was created because one king wanted to divorce and remarry.
There was never one unified organized Christian church, ever. Splintering or corruption as soon as an organized form with delusions of unique anointment crystallizes is inevitable due to it's inherent need to return to it's grass roots organic core.
With the reformation Calvin also tried utopia, it was a gigantic evil failure.
The crusades were only religious at face level and for propaganda purposes, in actual fact it was completely political/tribal.