In a number of tribes there seem to be cultural memories of these long migrations, encapsulated in their traditional mythologies - though these aren't really transcribable into written histories. There is, however, archeological evidence of human occupation in Peru dating back to around 15,000-20,000 BC, concentrated in the Ayacucho Valley , where these early Peruvians lived in caves or out in the open. Around 12,000 BC, slightly to the north in the Chillon Valley (just above modern Lima), comes the first evidence of significant craft skills - stone blades and knives for hunting. At this time there were probably similar groups of hunter tribes in the mountains and jungle too, but the climatic conditions of these zones make it unlikely that any significant remains will ever be found.

The difficulties of traversing the rugged terrain between the highlands and coast evidently proved little problem for the early Peruvians. From 8000 to 2000 BC, migratory bands of hunters and gatherers alternated between camps in the lowlands during the harsh mountain winters and highland summer "resorts", their actual movements well synchronized with those of wild animal herds. One important mountain encampment from this Incipient Era has been discovered at Lauricocha , near Huanuco, at an altitude of over 4000m. Here the art of working stone - eventually producing very fine blades and arrow points - seems to have been sophisticated, while at the same time a growing cultural imagination found expression in cave paintings depicting animals, hunting scenes and even dances. Down on the coast at this time other groups were living on the greener lomas belts of the desert in places like Chilca to the south, and in the mangrove swamps around Tumbes to the north.

An awareness of the potential uses of plants began to emerge around 5000 BC with the cultivation of seeds and tubers (the potato being one of the most important "discoveries" later taken to Europe); to be followed over the next two millennia by the introduction, presumably from the Amazon, of gourds, Lima beans, then squashes, peanuts, and eventually cotton. Towards the end of this period a climatic shift turned the coast into a much more arid belt and forced those living there to try their hand at agriculture in the fertile river beds, a process to some extent paralleled in the mountains.

With a stable agricultural base, permanent settlements sprang up all along the coast, notably at Chicama , Asia and Paracas , and in the sierra at Kotosh . The population began to mushroom, and with it came a new consciousness, perhaps influenced by cultural developments within the Amazon Basin to the east: cultism - the burial of the dead in mummy form, the capturing of trophy heads, and the building of grand religious structures - made its first appearance. At the same time there were also overwhelming technological advances in the spheres of weaving, tool-making and ornamental design.