For at least 600 years, until the late 15th century, the Chachapoyas amassed an extensive empire in the high Andes, building large cities, controlling complex trading routes and practicing a little-understood form of shamanism.
Nobody knows where the Chachapoyas came from, but starting about 1,300 years ago, they began to spread through an area known as the Ceja de Selva, or Eyebrow of the Jungle, reaching a population of about 500,000. They are renowned for their mountaintop citadels, such as Kuelap and Gran Pajaten.
Their downfall began around 1470, when the Inca began a war of conquest against them, resulting in their subjugation. Soon after, the Spanish came and conquered the Inca.
You know, I didn't think too much of this at first, but it's starting to sound more and more interesting.