In legend at least, the mantle of Teotihuacán fell on Tollan, or Tula, as the next great power to dominate Mexico. The Aztecs regarded the city they constructed as the successor to Tula and hence embellished its reputation – the streets, they said, had been paved with gold and the buildings constructed from precious metals and stones, while the Toltecs, who founded Tula, were regarded as the inventors of every science and art. In reality, it seems unlikely that Tula was ever as large or as powerful a city as Teotihuacán had been – or as Tenochtitlán was to become – and its period of dominance (about 950–1150 AD) was relatively short. Yet all sorts of puzzles remain about the Toltec era, and in particular their apparent connection with the Yucatán – much of the architecture at Chichén Itzá, for example, appears to have been influenced by the Toltecs. Few people believe that the Toltecs actually had an empire that stretched so far: however warlike (and the artistic evidence is that Tula was a grimly militaristic society, heavily into human sacrifice), they would have lacked the manpower, resources or any logical justification for such expansion.
One possible answer lies in the legends of Quetzalcoatl. Adopted from Teotihuacán, the plumed serpent attained far more importance here in Tula, where he is depicted everywhere. At some stage Tula apparently had a ruler identified with Quetzalcoatl who was driven from the city by the machinations of the evil god Texcatlipoca, and the theory goes that this ruler, defeated in factional struggles within Tula, fled with his followers, eventually reaching Mayan territory, where they established a new Toltec regime at Chichén Itzá. Though popular for a long time, this hypothesis has now fallen out of fashion following finds at Chichén Itzá that seem to undermine it.