The early Christians were primarily part of Judiasm, and later came from the Roman Empire. There was also a strong ethos of pacifism that is associated with the early church. I haven't heard of much violence in the early church so what are you referring to?
After Constantine made Christianity the Official State Religion, Christians were no longer fed to the lions in the Coliseum. Pagans took their place, their temples were destroyed, vandalized, or converted to Christian Churches.
Other examples can be found in the spread of Christianity by the early missionaries. When the kings of the Scandinavian countries converted to Christianity, it wasnt because they saw the light in a religious manner, but because of the benefits of trade with central and southern Europe. Any of their subjects that continued their pagan ways were converted by the sword.
Look at the pogroms and witch hunts. Look at the wars between Catholics, Protestants and other heretics.
I am not criticizing Christianity, but being honest about its roots.
I've suspected that his conversion may have been a shrewd ploy to tap into a movement that the State had no control over, and once the new and vigorous religion was adapted, all the temples to Jupiter and Hera and the other gods were reconfigured as Christian churches -- but I STRONGLY suspect that the "hierarchy" of priests DID NOT CHANGE!!
In this way, I think the "state-sponsored" Christian churches were corrupted from the beginning -- and much of the original virtues of the Christian church lost in the process...