How did Christianity affect history?

Answer 1

It did shine as a light through the dark ages and made civilisation progress. For better or worse, it did end paganism, but the persecution was aimed at Christians and not all persecution came from them. it was the cause as such of some religious wars, but its overall message is peace. the conflict between the church and state was there, but simply because the church popes were heretical and the state was mainly supporting the convicted 'heretics' who were actually good Christians.

Answer 2

The briefest summary of an immense topic, and limited to the effect of Christianity on history, but not the history of Christianity itself:

. The advent of the Dark Ages and the regression of civilisation
. The end of paganism in Europe
. Centuries of persecution, in Europe and eventually in the colonies
. Religious wars, particularly the Crusades
. Conflicts between church and state, kingdoms and popes