 with certain ethnohistorical sources, historian David Carrasco has argued that the preeminent function of the feathered serpent deity throughout Mesoamerican history was as the patron deity of the Urban center, a god of culture and civilization.
Quetzalcoatl as depicted in the Codex Borbonicus.
The worship of Quetzalcoatl sometimes included animal sacrifices, and in colonial traditions Quetzalcoatl was said to oppose human sacrifice.
Mesoamerican priests and kings would sometimes take the name of a deity they were associated with, so Quetzalcoatl and Kukulcan are also the names of historical persons.
One noted Post-Classic Toltec ruler was named Quetzalcoatl; he may be the same individual as the Kukulcan who invaded Yucatan at about the same time. The Mixtec also recorded a ruler named for the Feathered Serpent. In the 10th century a ruler closely associated with Quetzalcoatl ruled the Toltecs; his name was Topiltzin Ce Acatl Quetzalcoatl. This ruler was said to be the son of either the great Chichimeca warrior, Mixcoatl and the Culhuacano woman Chimalman, or of their descent.
It is believed that the Toltecs had a dualistic belief system. Quetzalcoatl's opposite was Tezcatlipoca, who, in one legend, sent Quetzalcoatl into exile. Alternatively, he left willingly on a raft of snakes, promising to return.
The Aztecs turned him into a symbol of dying and resurrection and a patron of priests. When the Aztecs adopted the culture of the Toltecs, they made twin gods of Tezcatlipoca and Quetzalcoatl, opposite and equal; Quetzalcoatl was also called White Tezcatlipoca, to contrast him to the black Tezcatlipoca. Together, they created the world; Tezcatlipoca lost his foot in that process.
Along with other gods, such as Tezcatlipoca and Tlaloc, Quetzalcoatl was called "Ipalnemohuani", a title reserved for the gods directly involved in the creation, which means "by whom we live". Because the name Ipalnemohuani is singular, this led to speculations that the Aztec were becoming monotheistic and all the main gods were only one. While this interpretation cannot be ruled out, it is probably an oversimplification of the Aztec religion.
The exact significance and attributes of Quetzalcoatl varied somewhat between civilizations and through history. Quetzalcoatl was often considered the god of the morning star, and his twin brother Xolotl was the evening star (Venus). As the morning star he was known by the title Tlahuizcalpantecuhtli, meaning "lord of the star of the dawn." He was known as the inventor of books and the calendar, the giver of maize (corn) to mankind, and sometimes as a symbol of death and resurrection. Quetzalcoatl was also the patron of the priests and the title of the Aztec high priest.
Most Mesoamerican beliefs included cycles of suns. Usually, our current time was considered the fifth sun, the previous four having been destroyed by flood, fire and the like. Quetzalcoatl allegedly went to Mictlan, the underworld, and created fifth-world mankind from the bones of the previous races (with the help of Chihuacoatl), using his own blood, from a wound in his penis, to imbue the bones with new life.
His birth, along with his twin Xolotl, was unusual; it was a virgin birth, to the goddess Coatlicue. Alternatively, he was a son of Xochiquetzal and Mixcoatl.
One Aztec story claims that Quetzalcoatl was seduced by Tezcatlipoca into becoming drunk and sleeping with a celibate priestess, and then burned himself to death out of remorse. His heart became the morning star.
It has been widely believed that the Aztec Emperor Moctezuma II initially believed the landing of Hernan Cortes in 1519 to be Quetzalcoatl's return. This has been questioned by some ethnohistorians, like Matthew Restall, who argues that the Quetzalcoatl-Cortes connection is not found in any document that was created independently of post-Conquest Spanish influence, and that there is little proof of a pre-Hispanic belief in Quetzalcoatl's return. Most documents expounding this theory are of entirely Spanish origin, such as Cortes' letters to Charles V of Spain, in which