The Toltecs were among the indigenous predecessors to the more famous Aztecs. Historians and archaeologists know far less about the Toltecs than the Aztecs, but it is believed that the Aztecs inherited many of their cultural practices, and many of their religious beliefs, from the Toltecs. In fact, much of what is known about Toltec culture has been gleaned from Aztec oral tradition, as recorded by Spaniards and even some modern anthropologists. Around 900 A.D., the Toltecs invaded what is now Mexico from the north, conquering and destroying the city of Teotihuacan. They established their own cultural and political centers at Cualhuacan and Tula. In general, the Toltecs were a highly stratified society based on the cultivation of maize. They built large monuments, practiced a polytheistic religion that included the god-king Quetzalcóatl, and may have, like the Aztecs, practiced human sacrifice. The Toltecs were aggressive militarily, and exerted political control over a number of surrounding peoples until their collapse under a series of civil wars and invasions by foreign tribes in the thirteenth century. One of these peoples, the Mexica, became known as the Aztecs. While partially responsible for the destruction of the Toltecs, they nevertheless revered them as ancestors, one of the reasons that Toltec legends survived in the oral traditions mentioned above.