Watch Channel 4 UK Documentaries online: Episode 2 Secrets of the Incas: War Against Time

As they wrote their accounts of the Inca empire, the Spanish conquerors recorded rumours of an Inca prophecy uttered in about 1434 by the elderly father of the first Inca emperor. The old man is supposed to have said that, within five generations of kings, the entire Andean way of life and its religion would be utterly destroyed. Secrets of the Incas presents completely new evidence taken from an Inca myth. In this, Dr William Sullivan believes, lies the key to the basis of the old man's prophecy and, indeed, to the formation of the Inca empire itself. This myth is nothing less than a dire warning of an impending precessional event that, to the Incas, predicted future ruin. The 'gate' or 'bridge' to the land of the ancestors - that is, the rising of the December solstice Sun with the Milky Way - was about to be washed away. Drawing on their ancient mythological database, the Incas reasoned - from the principle 'as above, so below' - that loss of contact with the ancestors, upon which their religious beliefs were founded, would mean their way of life would be destroyed on Earth. It was this prophecy that stirred the first Inca emperor to action: if time was merciless, it had to be stopped. So the entire Inca empire, which was less than a century old when the Spanish arrived, became involved in an attempt at cosmic regulation - to change the course of the stars by changing the course of human history on Earth: 'as below, so above.' Human sacrifice From the uttering of the prophecy to the moment of the Spanish conquest, five Inca emperors, through the use of ritualised warfare and human sacrifice, laboured unceasingly to arrest the precessional motion that threatened to disrupt and destroy the access of the living to the wisdom of the past. Every year in the Andes, each Inca tribe, which traced descent from a different constellation, would send a representative - an unblemished child - back to the stars (through human sacrifice) to implore the creator to stop the precessional drift that augured the end of everything. The Incas failed. Instead, with a sixth emperor days from a coronation that would nullify the power of the prophecy, the creator sent the Spanish, even as the bridge to the ancestors in the sky lay awash in the floodwaters of time.

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