You know, if those Jesuit priests hadn't busied themselves with raaping women and children and telling many FN & Inuit that they were going to helll .... maybe they wouldn't have been burned "at the stake". 

Some churches have taken responsibility for their actions, the Catholic church not so much.

Decimate means to reduce by 1 in 10.  Are you thinking Genghis Khan?  Because in areas like the NW Coast for e.g. there was raiding and temporary slavery - no decimation.  In fact across this continent, pre contact, trade was largely the name of the game.