Kukulkan was a post-Classical deity, perhaps introduced to the Maya by the Toltecs, who were influential at Chichen Itza and other centres in the northern Yucatan. Kukulkan is illustrated in the Venus pages of the Dresden Codex, which was compiled in the post-Classical period, probably after 1200 AD.
[With] the Itzas who settled Chichen Itza there ruled a great lord named Cuculcan, as an evidence of which the principal building [pyramid] is called Cuculcan. and that after his return he was regarded in Mexico as one of their gods, and called Cezalcohuati [Quetzalcoatl]. But Venus was important in Maya myth and astronomy much earlier.
He notes that Venus "remains close to the sun, always becoming visible a few hours either before sunrise over the place the sun will come up, or after sunset over the place it went down".
The Aztecs identified Venus as a dog who leads the sun, and the souls of kings, to the underworld.
According to the Manuscript of Serna, a missionary report from central Mexico, the natives "adored and made more sacrifices" to Venus than any other "celestial or terrestrial creatures" apart from the sun.