Best type of armor?

[Urnamma]

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 ;)

[Fondor_Yards]

What about the Ceannlann the Dosidataskeli and Uachtarach DuboGaiscaocha use? Just based off the armour ratings, it seems to be the best around.

[Watchman]

Layered, by what has been said here. Good scale over good mail plus of course the usual padding too, and the Dosidataskeli at least wear greaves to boot. Of course that's going to be pretty tough, but it doesn't mean the component layers themselves are "teh best around" - or that the setup would be even close to weight/price/protection-efficient.

[Bert Preast]

I wonder how much of the armour we know of was actually used on campaign. If you look at the conquistadores in the Americas though they were all armoured up to the nines for portrait calls, they ditched it all for simple cloth padding when they were engaged in serious bullying, raping and pillaging.

[Philippus Flavius Homovallumus]

For me armour is not good if it isn't efficiant. If you can only use it in one battle its no good, if you can't move more than ten paces its no good.

Incidently Lorrica Plumbatta is essentially what was used by Kats, and also by a fair number of Centurians. Obviously the version used by Centurians was less extensive.

[geala]

I wonder how much of the armour we know of was actually used on campaign. If you look at the conquistadores in the Americas though they were all armoured up to the nines for portrait calls, they ditched it all for simple cloth padding when they were engaged in serious bullying, raping and pillaging.

This is a very good question. In longer wars or campaigns or during routine duties the ease of movement, heat exchange and simple convenience win against the wish of better defence during the normally very few times of actual fighting. I imagine that less armour is worn in the frequently unexpected everyday fightings during patrol or skirmishes (not in pitched battles).

You can (try to) work against this human behavior with a strict discipline. So I don't think a Roman soldier of maybe 100 AD dared to march without his segmentata armour or even to "lose it accidentally".