horrors of this world in all ages have been committed by the religious
religious what? Certainly not religious Christians.
In fact the worst of all have been the fanatic non religious ideologies including the spectrum of Communist systems. Perhaps as evil are the self described ROP-the cult founded by Mohamed.
Sorry, but...You're kidding, right? Ever heard of the Crusades?
This site is decidedly anti-Christian, but its list of atrocities is one of the more comprehensive ones on the Net.
Having said that, in CURRENT times the Islamic faith is certainly responsible for the vast majority of atrocities.