Which most accurately describe the involvement of the catholic church in the crusades? (select all that apply.) after 100 years of fighting over jerusalem, the catholic church also waged war in europe against christians who did not follow catholicism. protestants led by martin luther used a campaign called the crusades as a way to break free from the catholic church. the knights templar were an order of crusaders approved by the pope and ordered to protect christian pilgrims traveling to the holy land. the crusades was a term used by the eastern orthodox church to describe its schism from the roman catholic church.