Old Gods, Ghosts, and 2012 Prophecies
The history of Chichen Itza itself is bathed in blood. The Mayan's were deeply religious and believed that it was a great honor to die for the gods. In the Popul Vuh, the Mayan Bible, the Mayan's lay out their faith in sometimes tedious details. Their faith was deep and long and they were willing to die for it. In fact, some of the best athletes that competed in the famous ball courts were sacraficed. The Mayan's didn't fear death and see sacrafice with dread and horror. They saw death as a passage to the next world. Chichen Itza was the site of mass sacrafices.
Chichen Itza may have also died in violence. Some archeaological evidencs shows that in 1221 a great civil war may have contributed to the disappearance of Mayan Culture in the great cities at the time. By the time the Europeans saw Chichen Itza, it was already a ghost city.