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The Aubin Codex is a pictorial history of the Aztecs from their departure from Aztlán from the Valley of Mexico of "Ca," composed at different dates and by different authors, with drawings and Nahuatl text. It begins with the migration from Aztlan in 1168 A.D. and continues with the dynastic history of Tenochtitlan and colonial events to 1608 A.D. The final pages list the pre-conquest and colonial rulers of Mexico-Tenochtitlan to about 1607. There is a 52-year calendar wheel in rectangular format on fol. 1 and the first page bears a title in Nahuatl and the date 1576.
Among other topics, the Aubin Codex has a native description of the massacre at the temple in Tenochtitlan in 1520. This is part of the Aztec account:
Here it is told how the Spaniards killed, they murdered the Mexicas who were celebrating the Fiesta of Huitzilopochtli in the place they called The Patio of the Gods.
At this time, when everyone was enjoying the fiesta, when everyone was already dancing, when everyone was already singing, when song was linked to song and the songs roared like waves, in that precise moment the Spaniards determined to kill people. They came into the patio, armed for battle.
They came to close the exits, the steps, the entrances [to the patio]: The Gate of the Eagle in the smallest palace, The Gate of the Canestalk and the Gate of the Snake of Mirrors. And when they had closed them, no one could get out anywhere.
Once they had done this, they entered the Sacred Patio to kill people. They came on foot, carrying swords and wooden and metal shields. Immediately, they surrounded those who danced, then rushed to the place where the drums were played. They attacked the man who was drumming and cut off both his arms. Then they cut off his head [with such a force] that it flew off, falling far away.
At that moment, they then attacked all the people, stabbing them, spearing them, wounding them with their swords. They struck some from behind, who fell instantly to the ground with their entrails hanging out [of their bodies]. They cut off the heads of some and smashed the heads of others into little pieces.
They struck others in the shoulders and tore their arms from their bodies. They struck some in the thighs and some in the calves. They slashed others in the abdomen and their entrails fell to the earth. There were some who even ran in vain, but their bowels spilled as they ran; they seemed to get their feet entangled with their own entrails. Eager to flee, they found nowhere to go.
Some tried to escape, but the Spaniards murdered them at the gates while they laughed. Others climbed the walls, but they could not save themselves. Others entered the communal house, where they were safe for awhile. Others lay down among the victims and pretended to be dead. But if they stood up again they [the Spaniards] would see them and kill them.
The blood of the warriors ran like water as they ran, forming pools, which widened, as the smell of blood and entrails fouled the air.
And the Spaniards walked everywhere, searching the communal houses to kill those who were hiding. They ran everywhere, they searched every place.
When [people]outside [the Sacred Patio learned of the massacre], shouting began, "Captains, Mexicas, come here quickly! Come here with all arms, spears, and shields! Our captains have been murdered! Our warriors have been slain! Oh Mexica captains, [our warriors] have been annihilated!"
Then a roar was heard, screams, people wailed, as they beat their palms against their lips. Quickly the captains assembled, as if planned in advance, and carried their spears and shields. Then the battle began. [The Mexicas] attacked them with arrows and even javelins, including small javelins used for hunting birds. They furiously hurled their javelins [at the Spaniards]. It was as if a layer of yellow canes spread over the Spaniards.
The Spanish version of the incident says the conquistadors interrupted a human sacrifice in the Templo Mayor; the Aztec version says the Spaniards were enticed into action by the gold the Aztecs were wearing. This prompted an Aztec rebellion against the orders of Moctezuma.
Also called "Manuscrito de 1576" (“The Manuscript of 1576”), this codex is held by the Bibliothèque Nationale in Paris. A copy of the original is held at the Princeton University library in the Robert Garrett Collection there. The Aubin Codex is not to be confused with the similarly-named Aubin Tonalamatl [def: The tonalamatl is a divinatory almanac used in central Mexico in the decades, and perhaps centuries, leading up to the Spanish conquest. It is Nahuatl in origin, meaning "pages of days".]
