Quote Originally Posted by Laundreu
I should be writing my 'Brief History of Russia' final paper and not answering this, but...

It's not an answerable question! It really depends on what you most value when equipping your troop(s), really. If it's cost, then (depending on the era) you might go with a chain haubergeon, or cuir buolli (boiled leather), or similar. In terms of sheer defensive power, the articulated plate of the 1500's or so are essentially the best available, worldwide. Of course then some bright bastard figured out the hand-gun thing and all of a sudden wearing 60-90 pounds of armor was pretty useless - that bullet ain't stopping for sheet metal!

(Also, kevlar is not proof against knives/spears/swords/piercing weapons in general, just some lower-power bullets.)

This is largely true. I will note that there is no 'best' form of armor. Scientific testing has to prove which is better in what situation is a daunting task that I happen to be taking up in a forthcoming book ;)