Ross Hassig notes that the Aztecs had defensive weapons such as quilted armor, helmets, and shields.
Ross Hassig, Aztec Warfare: Imperial Expansion and Political Control (Norman, Oklahoma: University of Oklahoma Press, 1988), 85-88, 90
DEFENSIVE WEAPONS
Aztec defensive weapons included shields, helmets, and various types of body armor. Aztec military shields (yaochimalli) were of a variety of designs and materials, with many being made of hide or plaited palm leaves (see Figs. 4, 5, 7,13,15,31—33). One conquistador described shields, called otlachimalli, made of strong woven cane with heavy double cotton backing. An early account describes shields of split bamboo woven together with maguey fiber, reinforced with bamboo as thick as a man's arm, and then covered with feathers. Other shields called cuauhchimalli, were made of wood. Some shields were made with a feather facing over which was laid beaten copper. One type of shield was constructed so that it rolled up when it was not needed in fighting and was unrolled to cover the body from head to toe. Shields were covered with painted hide, feathers, and gold and silver foil ornamentation. The feather ornamentation varied by color, type, and design, according to the owner's status, merit, and so forth. The Aztecs used round shields, although square or rectangular examples are found throughout the classic and early postclassic in the Maya area, Gulf coast, and at Cacaxtlan (present-day Cacaxtla, Tlaxcala).
As part of the royal fifth, Cortés sent the king a shield of wood and leather with brass bells on the rim and a gold boss with the figure of Huitzilopochtli on it. The handle had carvings of four heads— a puma, a jaguar, an eagle, and a vulture. As the Anonymous Conqueror cautioned of the Aztec shields sent to Spain, many were of the type used in dances and ceremonies (mahuizzoh chimalli) and not the sturdy war shields (see fig. 12). One shield examined by Peter Martyr d'Anghera in Spain was made of stout reeds covered with gold, and the back was lined with a jaguar skin. The lower part of the shield was decorated with a feather fringe that hung down more than a palma (0.209 meters or 8.2 inches). The hanging border of feathers was a common feature, and, though appearing fragile, it afforded additional protection to the user's legs. Such feather fringes could easily stop a spent projectile and deflect others, and the feature predates the Aztecs, being depicted in murals at the classic site of Cacaxtlan, at Teotihuacan, and among the classic Maya. They were probably intended primarily for protection against projectiles and not against clubs or swords.
The feather workers of Tenochtitlan made shields, and as part of their tribute the Aztecs received shields covered with fine, many- colored feather work and gold, depicting weapons, gods, kings, and scenes of great deeds in the past. These were made of fire-hardened sticks so strong and heavy that, reportedly, not even a sword could damage them. According to the conquistadors, a crossbow could shoot through them but not a bow.
The two feather shields in the Württembergisches Landesmuseum in Stuttgart are 0.71 and 0.75 meters (28 and 30 inches) in diameter, respectively, and have 3-millimeter (0.12-inch) foundations of wood strips bound together by fine interwoven cords. Four round sticks, 12 millimeters (0.47 inches) in diameter, cross the shields horizontally, and to these sticks and the leather patch on each shield are attached two leather handles. The outer surfaces of the shields are covered with thick parchment, covered with feathers glued to the surface.
Quilted cotton armor (ichcahuipilli) was a common element of battle attire in Mesoamerica (see figs. 31-33). It was constructed of unspun cotton tightly stitched between two layers of cloth and sewn to a leather border. The belief that the cotton was soaked in coarse salt to strengthen it derives from de Landa; but this account is unsubstantiated elsewhere, and Gates thinks this is a misinterpretation of taab, "to tie," for tab, "salt," and that the cotton was tied or quilted, not salted.
The ichcahuipilli was so thick (one and a half to two fingers) that neither an arrow nor an atlatl dart could penetrate it. It was made in several styles: a type of jacket that tied at the back, a sleeveless jacket that tied in the front, a sleeveless pullover that hugged the body and reached to the top of the thigh, and a sleeveless pullover that flared and reached the midthigh. As with their other weaponry, the Aztecs received some cotton armor in tribute.
The war suit (tlahuiztli suit) encased not only the torso but the arms and legs as well in long sleeves and leggings (see figs. 4, 5, 7,15, 31, and 32). These suits were not padded but were worn over the cotton armor. They existed in many different types; twelve are recorded as having been received as tribute. Despite appearing like animal skins, the suits of noble warriors were made of feathers sewn to a backing fabric. Only meritocratic nobles wore tlahuiztli suits of animal skins. Both types of tlahuiztli suit afforded some protection from projectiles, especially the body if the wearer was also protected by the ichcahuipilli, but the limbs were also protected, though to a lesser extent. The feathered garments were finer and of higher status. The slick surface of the feathers may have offered greater protection than would skins, especially against glancing blows, and depending on the backing, these suits were probably lighter and cooler.
In addition to the jacketlike top, leggings were worn. They offered the same protection provided to the upper limbs, since there was no cotton armor below the torso proper. But the legs were not major targets with the weapons in use, and the arms were most endangered by the force of blows rather than by the cutting power of the weapons used. Tlahuiztli suits apparently predated the Aztecs; a jaguar suit worn by a warrior is depicted at classic El Tajin.
Over their cotton armor some warriors—apparently the war leaders—wore feather tunics (ehuatl) (see fig. 13). Not as common as the tlahuiztli suit, the ehuatl was used primarily in the areas to the east of Tenochtitlan, stretching from Tetzcoco to Tlaxcallan. The tunic was fashioned of cloth over which feathers were set in rows. It had a hanging border of feathers and it resisted lances, arrows, and even swords. Because it lacked sleeves and leggings, however, the ehuatl appears functionally inferior to the tlahuiztli suits, and its continued use may have been due to its divine associations, as many gods bearing arms are depicted thus clad. Examples are shown in murals at Teotihuacan and in carvings at early postclassic Chichen Itza.
Some warriors (mostly higher nobles) also wore other body armor. Among these were armbands (matemecatl) and greaves (cotze-huatl) of wood, bark, or very thin gold; both were covered with leather and feathers. There were also wristlets (matzopetztli) (see fig. 13). These pieces were worn with the ehuatl but were of little protective value.
Some helmets made of wood and bone were highly decorated with feathers, while others were made of the heads of wild animals—wolves, jaguars, and pumas—over a frame of wood or over quilted cotton, with the wearer gazing out from the animal's opened jaw.
Some warriors wore a wide breechcloth (maxtlatl) that covered their thighs. Over this was often worn a hip-cloth. Sandals (cac-tli) were also worn by some of the warriors.