isn't it true?

I think you are ignoring that atheism has also killed, and many more than religions. Examples: Communism, Fascism, protestants. Also about the crusades, the muslims were killing the christians there for no reason before it started. About the indigenous from america, they were not the peaceful fellows history claims they are. They actually were very hostile and did many things to their enemies and even their own people.Also, its not the religion that killed, its the people who claimed that they were with God but actually had different intentions.

No

How?

wars

Just plain conflict between countries was automatically caused by religion? That makes no sense

no, i'm asserting religion, through conquests, wars, hatred and going after innocent people killed more than religion "saved".

And that was during a time of those who had the most power within the religion abused the power.

Such as the crusades, it was just power being abused

A lot of wars were religion vs religion.

Which was caused by abuse of nes religions leaders