While we don’t know the exact equipment of each Aztec military order, they definitely wore armour. This is attested to in several Conquistador accounts, including the Anonymous Conqueror who said:

'The armor which they use in war are certain loose garments like doublets made of quilted cotton, a finger and a half thick, and sometimes two fingers; they are very strong. Over them they wear a doublet and hose all one garment, which are corded behind. This garment is made of thick cloth and is covered with a layer of feathers of different colors, making a fine effect. Some companies of soldiers wear white and crimson, others blue and yellow, and others again of different styles. The Lords wear over everything garments like short jackets, which with us are of chain mail, but theirs are of gold and silver gilt. These feather garments are in proportion to their weapons, for neither arrows nor darts pierce them, but are thrown back without making any wound, and even with swords it is difficult to penetrate through them. To guard the head they carry things like the heads of serpents, tigers, lions, or wolves, with open jaws, and the head of the man is inside the head of the creature as if it was being devoured. They are of wood covered over with feathers and with jewels of gold and precious stones, which is a wonderful sight. They use shields of various kinds, made of good thick reeds which grow in that country, interwoven with cotton of double thickness, and they cover them with precious stones and round plates of gold, which makes them so strong that nothing can go through, unless from a good crossbow. Some arrows it is true pierced them, but could do them no harm. And because some of these shields have been seen in Spain I say they are not of the kind borne in war, but only those used in the festivals and dances which they are accustomed to have.'

Now, this is quite a quote. Nevertheless, it is informative as it does not merely tell us what the Aztecs wore, it tells us how effective the equipment was. The basis of the armour cotton, and it was effective enough to deter even European weapons. The text also informs us that the animal heads, such as Jaguar heads for Jaguar warriors, were not the real deal, but wooden imitations. This applies to the costume as a whole, which were made out of coloured feathers. The Aztecs did use actual jaguar skins, but these were most likely reserved for rituals. In other words, it was part of, what we would call today, the dress uniform. The Anonymous Conqueror also notes that the Aztecs had decorative shields for such occasions, supporting this interpretation. However, I think the most interesting detail is the use of metal on helmets and jackets. It is strange that the Aztecs used gold and silver as protection though, considering how soft those metals were. There are two possible explanations. First, that the precious metals were not intended for protection, but for identification. Silver and gold not only revealed the social status of the warrior, but it could also have told others who was in command. Second, the Anonymous Conqueror may have been mistaken, and the armour was actually copper and bronze. Such protection would be expensive, and thus restricted to nobles and commanders. Of course, neither are mutually exclusive.

What did this armour look like? We have some depictions of Aztec war suits, mainly from the Codex Mendoza. Here are some pics Alas, there are no Jaguar Warriors depicted in the codex. There are pictures of them in the Florentine Codex however (which you can see on the page). But they are not as detailed as the Mendoza ones.

The best (or at least most accessible) modern summary/compilation of Aztec armour comes from Ross Hassig’s Aztec Warfare. His explanation is very easy to understand and follow. The basic body armour was the ichcahuipilli, which was basically a cotton shirt about two fingers thick. For elite warriors this was then covered by a tlahuiztli, which was a cotton war costume, decorated with feathers. This armour was also made out of cotton, although it was less padded. This gave less protection, but still allowed for the extremities to move flexibly. Warriors also wore padded leggings and arm braces, also made from cotton (or possibly deer leather). Elite commanders wore an ehuatl, or feathered tunic, in place of a war suit, although it is not exactly clear why. Armour was reinforced with metals, leather, and possibly even wood (I think cane may have been used for this purpose, but cannot confirm it). As for helmets, the wooden animal helms have already been mentioned. However, most soldiers seems to have worn a conical, cotton helmet, which is commonly depicted in the codices. John Pohl’s Aztec Warrior has some good illustrations of what the equipment may have looked like. Exact style of course, would have varied between different regions, and over time.

So, what might a Jaguar Warrior have worn? While we don’t have the exact description, this can give us a pretty good idea. The core armour would have been a thickly padded cotton ichcahuipilli. Over this they would have worn a tlahuiztli decorated to look like jaguar skin. They would have had a reinforced wooden helmet, and cane and leather gloves and greaves. They were definitely not shirtless! Instead, they were well-protected from the types of weapons they expected to face (and even some they weren’t) while suiting the climates of Mesoamerica.

Sources:

The Anonymous Conqueror 1917 Narrative of Some Things of New Spain and of the Great City of Temestitan, Mexico, (Edited by Christensen, Alec), Obtained from: http://www.famsi.org/research/christensen/anon_con/ Accessed 5, March 2012.

Berdan, Frances F. and Anawalt, Patricia Rieff 1992a The Codex Mendoza Volume II: Description of the Codex, University of California Press, Berkeley. 1992b The Codex Mendoza Volume III: A Facsimile Reproduction of Codex Mendoza, University of California Press, Berkeley.

Cervera Obregón, Marco Antonio 2011 Guerreros Aztecas, Ediciones Nowtilis, S.L., Madrid.

Hassig, Ross 1988 Aztec Warfare: Imperial Expansion and Political Control, University of Oklahoma Press, Norman.

Pohl, John 2001 Aztec Warrior: AD 1325-1521, Osprey Publishing Ltd, Oxford.