The archbishop of Canterbury was only stating the obvious when he recently maintained that "most Christians would now say that...the crusades...or the religious wars in Europe in the sixteenth and seventeenth centuries were serious betrayals of many of the central beliefs of the Christian faith."

But for centuries the overwhelming majority of Latin Christians believed that qualified men had a moral obligation to take part in crusades and the modern consensus begs the question why most devout Christians from the eleventh to the seventeenth centuries saw no contradiction between taking the cross and their religion.

What motivated them?

Why do we think so differently?

What anyway are ‘the central beliefs of the Christian faith’ in relation to the use of force?