Can anyone here shed some light on the concept of using wood as armor, as to if it was ever commonly done? It seems like a good idea, on paper, for the following reasons:

1. It's Cheap- Wood is pretty much everywhere in the form of trees and is definitely easier to find than, say, leather or metal. It's so common that it is burned as fuel! Theoretically it could cost a fraction of the money to equip a garrison with wood plate (out of just a few trees) compared to mail or scale armors.

2. It's Easily Worked- Carpentry is a much broader skill and takes a lower level of intensive knowledge than mailing or working plate armor. Wood only needs to be sculpted and finished. Ancient carpenters would definitely have these skills.

3. It's Durable: Not as much as metal, but wood provides a hard surface to absorb the shock of blows and, given a hard wood such as oak, is not easily pierced. Leather, cloth, and chain don't give this same level of protection.

4. It's Light: It's pretty light when compared to the protection that it offers from blunt trauma and piercing.

5. It Was Used In Shields: So why not for other pieces of armor?

What I'm trying to suggest is that wood seemed like a no-brainer for ancient and medieval armies. A peasant or foot soldier who would otherwise be fighting in his clothes or some padding could have had a much higher survival rate in wood armor that while cheap provided good protection. Despite this, I have seen absolutely zero evidence on the internet for wood armor, with three exceptions:

1. The Inca definitely used it as wood plates sewn into quilted padding in a similar style to modern day body armor. This was recorded by the Spanish when they fought the Inca.

2. The board breaking tradition of Korean martial arts originated as training to punch through wood armor, or so Iv'e heard.

3. The Chinese for a time used armor made of mulberry paper, that while not truly wood was surprisingly effective.

Any theories, links, or other info related to wood armor would be appreciated.

I mostly know medieval european armour, and I don't know of any examples of wood armour being used.

One thing that isn't mentioned in your list is that cloth armour is cheap and effective (period accounts in the later 15th century mention it being sword and mostly arrow proof), and medieval europe and many other civilizations had lots of cloth.

There is textual evidence that the Byzantines used wooden armour.
A book I have hypotheticaly illustrates them in the form of splints, which would be a plausible form for armour made of wood.
Plywood is a period material. Splinted armour made from light plywood would be worthwhile investment.

Yeah the Strategikion mentions wooden greaves but doesn't suggest how they were made.

Bamboo has been used in armor.

I am not trying to be a smart %$@ here but would a shield not be considered armor? I would have to say that all the reason you have mentioned in favor of wood would all justify its extensive use in shields. So basically, if we consider shields as armor then that is my answer to your question.

I would think that wood would offer good protection against blunt weapons, but that pointy or sharp weapons would do quiet a number on it. Plus I wouldn't want to be the guy wearing wood when facing opponents using axes. :)

Looks like an early kendo bogu to me. I don't see what else it could have been used for.

This bogu is pretty much the same actually. http://www.hifreeads.co.uk/real-antique-kendo...-4017.html

Makes no doubt to me that it wasn't used on the battlefield.

http://www.youtube.com/watch?v=VsZnTCQptWc

I found this video called "Shield Tests" from the Weapons That Made Britain series. While the series does fudge up a few things when it comes to historical accuracy it seems to be one of the better programs out there. (At least better than Deadliest Warrior.) I think that it raises a few interesting points about shields and wood armor in general:

1. The linden wood shield used is indeed vulnerable to splitting when faced by attacks from both axes and arrows. Keep in mind that the wood used is both thin (1/8 in.) and made of a single plank as opposed to overlapping planks as used by Roman and Viking shields.

2. The rawhide used on the second shield does a good job to keep the shield together and protect the wood from splitting apart. It is proof against both the axe and the bow although it is heavier. The dane axe does not penetrate either, although the energy transferred would no doubt incapacitate somebody in a wood and rawhide cuirass. It seems pretty obvious that a blow like that would just about kill anyone in cloth or leather armor. At least the wood gives a solid surface to absorb the impact.

3. The lenticular shield successfully repels the dane axe attack thanks to its weight and rounded shape. By being rounded it deflects some of the axe's energy and the wood bends but holds firm.

By the details presented by this video it seems that wood by itself would not be sufficient since it could easily split but wood layered against the grain and covered with rawhide does a good job against period weapons and while heavy gives more than adequate protection. IMHO a wood cuirass definitely seems workable although I wonder if it would be any lighter than an iron one. Dark Age warriors must have known something about combat that led them against using wood armor despite its potential benefits. Maybe the armor and shields in use gave good enough protection or perhaps it was more of a mobility issue of lugging around 25 lbs of wood all day.

I agree with Dan 99.99%, almost no low tech material is stronger for weight than metel, especialy if you are talking steel.
The 0.01% where I don't agree with Dan is that there are 1 or 2 possible exceptions, but they are so outlandish that they actually re-enforce what he is saying.
From memory, spidersilk is stronger than a steel wire of the same diameter, and probably comes under the heading "low tech". If someone were to take individual threads of spider silk and turn them into a twine, and then make cloth out of them and make a padded armour out of it, it would provide exceptional protection for weight. This scenario is "possible" but would be so ridiculously, painfully laborious as to be dismissed. I do not even want to think of the man hours that would be involved in something like that.

Primitive or pre-historic Neolithic cultures might have used wood armour since they wouldn't have metal.

Hard to prove since I don't think any wood armour has been found from pre-historic times, but it does seem at least possible when little else was available except other natural materials like heavy hides.

As others have mentioned there was coconut fibre armour used in the South Pacific and I seem to remember some wooden armour used by Alaskan natives.

There's also wooden armour from Indonesia. The most famous examples are Toraja. ("Toraja armour" makes for a fine google or google images search term.) Usually sleeveless vests or woven fibre (palm or rattan?) with plates, discs, or scales attached. Plates can be wood or bone, or hard flat seeds.