This structure was built between 900 and 1100 AD around the merger of the Mayan people and the Toltecs. The Mayas were a peaceful, agricultural society. The Toltecs were a society of warriors. It is believed that the Platform of the Skulls was built for the purpose of intimidation based on principles integrated from the Toltec culture. Platform of the Skulls. Xichen Itza, Yucatan, Mexico