THE ORIGIN OF CHIVALRY

My understanding is that chivalry saved Europe. Will someone correct me if I'm wrong? Here's the way I heard it...

The early Christians were pacifists, which is fine except Europe in the Dark Ages needed muscle to defend itself against Scandanavian, Mongolian and Islamic predators. The newly Christianized German barbarians came up with an idea that would simultaneously satisfy the pacifists and still allow Europe to re-arm, and that idea was built on the old German idea of knighthood.

The new idea was that the pacifists were right...yes, it is wrong to kill...but only if you do it to further your own ends. It's not wrong if you kill unsefishly, for someone else's sake and not your own. The new synthesis was called chivalry and the first knights of this type (there were other types) were widely respected for their high ideals. Without these knights Europe would surely have sucumbed to internal wars and outside predators.

So, have I got it right? I can't remember where I read this.