Quetzalcoatl (i. e., the serpent or the twin with peacock or trogon feathers), the name of a mythical personage introduced into Mexican mythology by the Huastecas, a branch of the Mayas, who came, according to tradition, in boats along the coast and settled at Pánuco, without opposition from the former possessors, though in course of time they held their own against the Otomies, Nahoas, and Chichimecas, till they were finally conquered by the great monarch Nezahualcoyotl. The Natchez are supposed to have been also a part of this body of emigrants. This mythical personage appeared in a long white robe, holding a staff, and introduced the honors paid to the cross. He taught the people many arts, introduced a system of worship, and finally returned to Yucatan according to Mexican tradition, though in Yucatan, where he is known as Cuculcan, they make him return to Mexico. The accounts given of him are not always consistent, and may apply to a series who bore the name. He was ultimately honored as a god, and especially as the god of rain.

The religious ideas introduced by him were not confined to the Huastecas, but extended to the whole Mexican empire.