What it was:

Dimensions: Mail armor would be fitted to the different parts of the body with rings of around 1/2 inch in size. A plate armor suit had to cover the entire body and required around 40 labs of iron(3). Early helmets of the 1200s could weigh up to 14 lbs(5). One example of a bascinet was been measured to see how thick these helmets would be. It was German, produced in the 1380s, and was thickest in the top front (3.81 mm), and thinnest on the visor (1.27 mm). A cuisse from Italy, 1390, was around 1.78 mm. No breastplates of that time period are available to measure but one from the 1470s was about 2.03 mm thick(6). This shows that the head would be more protected than the chest. A breastplate would be thickest in the center front and all armor thicker on the left side since not protected by a weapon(3). A full set of plate armor could weigh from around 25 to 100 lbs(8).

How it worked: Made to protect the body against most weapons. It would encase the person in a strong material (preferably metal) that could block a blow and deflect it so that there was no puncture and not much crushing damage done to the person.

Materials: Started out with leather and cloth, and then slowly changed to iron. This iron would be case-hardened with charcoal to form it into steel.

How to make it:

  • Mail armor was made by first cutting metal into thin rods and then drawing them through smaller and smaller holes to make wire. This wire would be wrapped around a rod the size they wished the rings to be, and then cut with wire cutters to make hoops. These would then be heated and pressed, overlapping the ends and adding a hole for a rivet, so that the ring could then be hammered together with rivets to connect to other rings. Sometimes rings were made already closed with a press from full sheets of metal(2).
  • Plate armor needed specialists in many different areas:
    • The iron first had to be mined and melted down into bars and then sent to the armorers.
    • A hammer man (usually an apprentice or journeyman) would then forge the iron, heating the metal up and using different poles topped with casts that were shaped like the different pieces of armor to hammer the metal into the correct shape, cutting it down to the size of the person it was meant for and turning in the edges to prevent scratches.
    • A millman or polisher would then take this shaped metal that had dents and was blackened by the fire and, using a water mill attached to a grinder, would polish the metal and get it to the right thickness.
    • A finisher (often the master, since this was one of the hardest jobs) would assemble all the pieces and add padding and leather buckles.
    • If the plates were to be decorated, they were sent to an artist, such as an etcher, gilder or painter.
  • The iron was first pounded by hand, but later armorers used tilthammers, which were powered by water mills. The different types of anvils for the different shapes were each called after the pieces they would make (i.e. creste stake-helmet) and there were different hammers for each job.
  • Metal was worked cold for basic shaping, but then often case-hardened. Case-hardening is the process of changing iron into steel by addin carbon. The iron would be wrapped in lard, goatskin or charcoal and cooked for a long time.
  • The steel could then be made stronger by quenching (heating and then dropping in cold water or oil)(3).

Parts of armor:

  • With mail armor a knight would wear a padded undergarment (an aketon/gambeson) then a mail shirt that went to the knees (a hauberk); this sometimes had extended sleeves that ended in mittens for the hands. Some knights wore a hood of mail as well, called a coif. Knights would often put a surcoat over the mail to both keep it dry so as not to rust as well as to display their coats of arms(2).
  • Knights would wear some form of helmet that came in different shapes and later incorporated both chain and plate armor(2).
  • Later plates added to the chain included polynes for the knees, shin and foot guards, courters, which were circular disks for the elbows, besagews, the same thing for the shoulders, then full arm, leg and hand protection(8).
  • A full suit of armor like the steel skins from the 15th century included a soleret or saboton these were a foot cover which included lames which were plates that overlapped downward to the toe. The leg then was covered by a greve to wrap the calf, lames over the knees, and cuisses for the upper thighs. The breast plate, or cuirass fastened at the shulders and sides and often had a short skirt to defend the hips. Sometimes these had moveable rivets that could give more motion at the waist. The forearm had a vambrace, a tube which attached to an elbow guard and then a rerebrace for the upper arm with sliding rivets to a grooved shoulder collar. Gauntlets on the hands had more overlapping lames and would often be in mitten form rather than a full glove. Helmets came in many different designs including barbute, mostly used in Italy, covering all the head except for a T shape in the front for eyes and nose, the chapeau de fer like an armor brimmed had, and the salade used mostly by Germans, with a separate movable visor. Later on the armet helmet became the main helmet because it fit the head's shape very closely and could be opened with hinges to lift up the visor. The armor would sometimes include a codpiece, but this was more a status symbol than a useful piece of armor(8).

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When and where:

Dates it became popular: Mail armor started being used in the 10th century, but didn't really become popular until the 12th century. Plate armor slowly developed in the late 13th century, being most popular in the 1340s(3).

Dates it declined: Mail armor was used for a very long time, at least until the 17th century, since it was easy to produce, but fell out of primary battle use in the late 13th century. Plate armor fell out of use in battle by the late 1650s, but was used for formal tournaments and dress-up occasions for another century after(3).

Where popular: Armor popular throughout the world, with plate and chain most popular in Europe. It was most often made close, near good sources of iron, as in Germany. Milan was known as a major center for plate armor(3).

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Who made and how:

Person who made it: Armorers, (sometimes a blacksmith would help repair or make cheap armor) these men would be in a guild that was often very strict in promoting masters(3).

Where to get materials: Germany and upper Italy had good places to collect them. A good armory in 1544 needed around 244 lbs of steel for a year's worth of work, which cost about 15 pounds.

Cost: Plate armor cost depended greatly on whether it was made custom to fit or not, and then on the amount of decoration on the armor. In 1441 a ready-made suit sold for about 9 pounds, while in 1641 a custom-made one with lots of decorations for a prince went up to 340 pounds. Munitions armor (pieces like arm guards and breastplates) that were made in assembly-line fashin could be as cheap as 7 shillings(3).

Other things needed for it: Armor also needed joints to put it together, like buckles and leather straps. The armorer who mad it needed lots of charcoal to harden the iron and lots of fuel to heat up the metal. Often the armor was decorated and therefore gold, silver, acid for engravings, paint and other things were required. Armories tended to be near running water to power the hammers and grinders.

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Technological innovations:

What changes occured and when:

  • Armor started mostly with cloth and leather. People would make linen padded jackets whcih were often quilted. They also used leather, often boiled and then cooled into shape, which would harden it, making good, cheap armor. This was called cuir bouilli, boiled leather. If these pieces were not cared for (kept dry and oiled), they would crack and rot away(2).
  • From the tenth to early thirteenth century, mail armor became the most popular style. This started with leather with rings sewn onto the leather and then formed into full garments made of linked rings. Each suit would be made from around 30,000 to 250,000 rings of iron, brass or steel. Mail shops were organized very differently than the later plate armor shops. Since most of the work was very tedious, the apprentices would make all the links, and it was the master who would follow almost a knitting pattern, by adding or removing rings to shape, to put them together for a garment(2).
  • Men started without armor for their legs, but leather and slowly chausses (mail leggings) came into popularity(3).
  • Knight wore helmets that ranged from conical with a nose bridge early on, to cylindrical with only slits for eyes and breathing. They tried having helmets with flat hops, but decided rounded was better able to deflect the force of a blow(2). As plate armor came into fashion, mor knights used bascinets, conical helmets with attached camails (mail for just the neck) and visors.
  • Mail armor fell in popularity because it was very heavy, all resting on the shoulders, did not help protect from the weight of a bruising blow, and with the growth in strength of the longbow and crossbow, would often be pierced(2).
  • By the late 13th century, knights were adding flat plates of metal to their clothing, first small pieces sewn into a padded inner garment, and then later specific pieces shaped to parts of the body to protect the weaker spots like the knees and shoulders(2).
  • These small plates slowly expanded until plate armor covered the entire body, including the feet and hands.
  • Plate armor could be made harder by heating it to a very high temperature and then quickly quenching it in water or oil. Different types of cooling gave more strength, but less ability to sustain tension and deformation (cold worked metal is not heated at all, and elongation is the amount it can be deformed before fracture):(6)
    ConditionTensile StrengthElongation
    Cold Worked44 tons/sq. in.12%
    Quenched51 tons/sq. in.14%
    Slow cooled30 tons/sq. in.35%
  • Since quick quenching would make the material stronger, but more brittle, the best way to strengthen metal was to quench it and then slowly reheat it to a lower temperature and tempering the metal. This method was not always used since it took lots of time and materials. Instead, slack-quenching would be used, where the material would be heated and left to cool off for a short while and then quenched in oil(3).
  • Hinges started first with leather buckles and then changed to brass or steel hinges or staples with pins and hooks(3).

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How common a weapon: Almost all soldiers tried to have some form of armor. Most of the lower class had simple leather armor and cloth armor, although later on cheaper assembly-line plates, such as breast plates were available. Higher class soldiers and more successful ones were able to use a mix of leather, chain and plate, including a helmet. All knights had to have a full set of armor, either early on of chain mail, or later of plate.

Primary source quotes:


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One formula given for how thick plate armor had to be to protect you from a longbow arrow is the De Marre equation:


  • W=weight of projectile
  • d=diameter of projectile
  • V=velocity of projectile
  • x=angle of attack
  • t=thickness of plate
  • C and A are constants
  • When value on left side exceeds that on the right penetration occurs(6).
  • http://navweaps.com/index_tech/tech-033.htm

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Other Interesting Facts:

  • Saracens used a thick quilted padding with leather that would resist penetration and absorb impact. The Spanish used the same idea but with 4 inch felt(1).
  • The Mongols wore thick silk inner clothing which would not prevent arrows going into the body, but would not let the arrowhead go through the cloth, so it could easily be pulled out later(1).
  • Full plate armor was better because it could with its curves deflect arrows off its surface(4).
  • A problem with plate and ring armor was that sometimes it could block an arrow from killing a person but usually the arrow would go in just enough that it would get lodged in the armor itself, and have to be cut out. Chain would also let through splinters from arrows(1).
  • The types of iron available to work with were:
    • Wrought-iron: This was low-carbon iron that could be heated at around 700 degrees Celsius and then shaped into different useful tools, but had problems keeping an edge and was easily bent when cooled.
    • Cast-iron: This was high-carbon iron (3.5%) which would be made by a smelting furnace into a liquid form that then would be poured into different casts to create objects. The problem was that it was brittle and could not be shaped even when reheated.
    • Steel: Steel is formed from iron by making just the right amount of carbon go into the steel (around 1%). This was the strongest they could make the iron and it could hold an edge and be shaped when hot. The reason why not all materials were steel was that there was no way to precisely control the temperature of the furnace and the amount of carbon that got into the steel so instead many weapons would have a steel blade on an iron core(2).
  • To clean mail of rust it would be put in a barrel with coarse sand and rolled for about an hour(5).
  • Armor would often be tested in front of customers before it was sold to ensure that it would protect them. It would be shot with a crossbow, and this would leave a small dent(3).
  • Horse armor: A horse would sometimes be covered in armor, including a head piece called a chanfron which would often have a spike on the forehead. They would then have either overlapping plates (called crinets) or mail on the neck. The body was covered by a peytral, a plate-like apron hung from neck to withers. The rump of horse was covered by a crupper (a large plate) and the tail by a tube called a gardesqueue(8).

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Decoration and Styles:

  • Different patterns for mail armor included the basic European pattern of one in four, Japanese grid pattern, either in square or hex, or Persian one in three(7).
  • Italian armor was more often simple lines with a rounded form. German had a more Gothic form with lots of fluty flairs. Emperor Maximilian's armor from the 1500s was very grooved(4).
  • The ways of decorating plate armor grew gradually mor elaborate:
    • Engraving was the oldest decoration style but took too much labor and time, and therefore was not often used.
    • Gilding involved putting mercury on the plate to act as a glue and then laying down gold in patterns, and heating the metal to remove the excess mercury. This was very toxic.
    • Gold could also be added by painting on varnish and then putting down gold leaf, then drying, or by painting the material with gold dust.
    • the metal could be tinted a very pretty blue color by heating it up to 310 degrees Celsius and then quenching it.
    • The most popular way of decorating armor was by etching with acid. This was known as early as the 14th century. Armor was coated with an acid resistant varnish, wax, or tar, and then a design would be etched away, and the metal dipped into acid, and then turpentine to clean it. The design was then often blackened with oil. There are some examples by Germans of negative etchings.

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