In 1227, heading back to Mongolia after a victorious campaign against the Central Asians, Chinggis Khan died.
One legend has it that a funeral cortege conveyed Chinggis's body to northeastern Mongolia and buried 40 virgins and 40 horses with him. According to this legend, the grave was stamped down by the horses' hooves as a means of hiding the location of his tomb.
There is a second possibility, however, that Chinggis's body was simply allowed to lie were it fell. At this time in their history, the Mongols had not yet developed a tomb culture; in fact, they would only develop a tomb culture after they'd had greater contact with the Chinese and the Persians. Thus, Chinggis's body may have been left to be consumed by the animals.