Mail (also known as Maille, chainmail, ringmail or chain armor in modern times to distingish it form the postal services) is a variety of armor composed of a series of small interlocking metal (usually wrought iron or steel) rings. Though who invented it is not yet known in full, first instances of mail armor came up in Europe around 300BCE, used by both the Etruscans and the Celts. Either by learning of it from others, or by developing it on their own independently, chainmail would become one of the most common types of armor across Europe, the Middle East, India, Asia and the more developed parts of Africa.
Information about mailEdit
Mail is a labor-intensive form of armor to make. Even a mail vest will have thousands of individual rings, each of which need to be hand made one at a time. This is offset by several points. First of all, mail was a form of metallic armor which was made of iron, which is far more common than the alternative of bronze, which involved getting both copper and tin. Secondly, despite the fact that it took a fuckload of work to do so, making individual rings (or links) was not a particularly difficult thing to do. Though eventually you did see specialized linkmakers, the job could be done by your average generalized village smith if he had some appropriate gear and a little practice, and large amounts of labor could be put on the smith's apprentices, as the most difficult part of making mail is following patterns properly. Third, a suit of mail can easily be patched if damaged. Fourth: unlike plate armor mail can flow over the body allowing to protect otherwise hard to defend spots.
In terms of defense, mail has some advantages and disadvantages. Its biggest advantage is that it's excellent at defeating slashing sword attacks. Due to the interlocked nature of the rings a slashing blow has its energy spread out among the links, imparting limited energy to the wearer while keeping the sharp blade away from the body. This is double effective since mail is always paired with an undergarment to further protect against blunt attacks (known as a gambeson, an aketon, an arming doublet or simply padded armour). Against thrusts such as spears or arrows it will protect decently, against the attack which of course depends on what type of mail you are wearing, and what kind of weapon your opponent is wielding. A longbow shot or a piercing blow from a sharp sword might still break through (where it would get stuck in a gambeson with its 14 layers of linen). Further mail advantages are that its flexible for great mobility and is actually quite comfortable. In a fantasy context chain mail is one of the only types of armor we know for a fact will work against a monster since a Shark suit is pretty much just chain mail and it also used as protection when working with tesla coils and high voltage since it's, basically, a wearable Faraday cage. Just make sure your feet are properly grounded and that the electricity has no direct path through any of your vital organs.
Mail's major downside, however, is that it's worthless against blunt trauma. If hit directly by a high-impact weapon, like a hammer, axe or a falchion, the mail, rather then compressing, transfers that energy to the body under it for full damage, which is why it's paired with a gambeson, but a hard enough hit still won't be stopped by its padding. Furthermore, against some thrusting attacks the force would be so concentrated that only a few links would have force applied to them, removing the benefit of interlocking rings, breaking them apart and punching through the armor. A full size hauberk is very heavy, going up to as much as 20kg. And most of this weight is going to hang down from your shoulders. Whilst tightening a belt around your waist helps somewhat by transferring some of the weight from your shoulders and upper body to your legs, it creates its own set of problems, especially when lifting the arms for overhead swing.
Iron is a very good heat conductor, so mail can heat up or cool very rapidly depending on weather and even burn your skin if you do not put something under it to protect yourself, or over it to shield it from direct sunlight (which is one of the reasons the crusaders wore their signature tabards and skirts). Also don't even think of wearing it against bullets. The bullet just ends up dragging metal rings into the wound. Mail works a lot better against spalling, (small shards of metal thrown off the back side of another metal when hit hard enough) so WW1 tankers sometimes had mail face masks to protect their face and eyes.
Today, the sole purpose of mail as actual body armor is for divers as shark protection, and even then, you'd have to be crazy to not at least have an entire steel cage between you and a large shark just to be safe (they've found bits of actual plate metal in shark stomachs at times). It is also used by workers in meat plants who cut up a lot of meat slabs with really sharp knives. A small cottage industry exist making chainmail for historic recrationists and film (though plastic maile is more common in film as it's lighter).
Getting the name rightEdit
Yeah, *everyone* knows it's called "chainmail", right? Well, yeah and no. "Chain-mail" is a neologism, coined by some english jack-of-all-trades writer Walter Scott. In real world, historical peoples that used this armour had various and sometimes elaborate names, alas for us, in an english speaking world, the correct name is "maille" or "mail" (which was introduced to the dictionary by French-speaking Norman conquerors in 1066). To further annoy your DM, you could learn correct names for various scraps of mail, that make up the full suit.
- A mail shirt is called a hauberk if it features full length sleeves and reaches your knees or haubergeon if it's a shorter version.
- A full maille hood is called coif. If it's just a piece of loose mail attached to a helmet to protect the face or neck, it's called camail or aventail.
- Small patches of mail attached to a padded armour or arming jacket in strategic places are called voider. These were used to fill the gaps in plate armour (ie. armpits, neck and waist areas) before the advent of articulated "full plate".
- "Chainmail leggings" are chausses (/ʃəʊs/ or which-the-fuck-ever is the right way to pronounce it). Mail gloves are called mittons.
As is the custom and for maximum effect you should avoid using these terms with the word "mail" or "chainmail" in the same sentence. Example: "Fetch me an aketon with voiders and a pair of chausses, my stout yeoman if you please." to a shopkeeper in armour-selling shop.
How is it made?Edit
The rings were usually made of malleable iron. First it would be drawn into wires, then coiled up and cut into rings. Rings would then be annealed and hammered flat (important - most of the known mail uses the "flat wire" rings, akin in appearance to washers, instead of "round wire" rings so prevalent on the market right now), creating an overlap, where later, during the linking, a wedge-shaped rivet would be inserted. Many suits of mail were made using alternating rows of riveted rings and solid round washers of similar size. Whilst the former were hand made from wire, the latter were simply punched from a metal sheet. This reduced the workload enormously and made the whole thing stronger and less likely to break up. Rings would then be put together into lengths of narrow strips by apprentices, which would then be correctly linked by a master armourer, forming a desired piece of armour. Think of it as stitching a shirt from strips of cloth using more cloth, but instead use metal keyrings.
Anyway. This created a metal skin comprising alternating layers of flat "washers", which was highly flexible and reactive to applied force - the rings would "bunch up" at the point of pressure, effectively multiplying the amount of metal resisting the blow.
Using expansion/contraction techniques (which involves adding or removing rings in predetermined places when making the armour), the mail shirt can be tailored to the wearer. One of the few surviving suits of mail (15th century or so) narrows at the waist, expands for hips and thighs and is additionaly enlarged at the back, to allow leeway for shoulderblades and arm movement.
There are other known patterns of pure mail armour. A very rare european 8-in-2 ("The King's Mail") was essentially a doubled-up 4-in-1 and used sparingly since it was hard to make and rather inflexible. Two patterns are native to Japan, namely square 4-in-1 (so gusari) and hexagonal 6-in-1 (hana gusari). These were much less dense (in terms of rings-per-square-inch) than their european counterparts and also much less resistant to damage as they were usually made of non-riveted rings. For this reason the Japanese mail was usually either stitched to the backing cloth or sandwiched between other layers of an armour suit. We won't get into further detail on how good or bad the japanese mail is, since if you're genuinely interested in Japan, you'll know all about it anyway... and if your interest is slightly more than just scientific, you already know the details are irrelevant, since the japanese swords will make short work of any mail on the planet.