Historical Sketch of the Incan Peruvians
The Inca dominion, as the Spaniards found it, was instituted only about a century before the coming of the white man. Before that time Inca sway held good over scattered portions of the country, but had not extended over the entire territory which in later times was connected with the Inca name. That it was founded on the wreck of a more ancient power which once existed in the district of Chinchay-suyu there can be little doubt. This power was wielded over a space bounded by the lake of Chinchay-cocha on the north and Abancay on the south, and extended to the Pacific at the valley of Chincha. It was constituted by an alliance of tribes under the leadership of the chief of Pucara, in the Huanca country. A branch of this confederacy, the Chanca, pushing southward in a general movement, encountered the Inca people of Colla-suyu, who, under their leader, Pachacutic, a young but determined chieftain, defeated the invaders in a decisive battle near Cuzco. In consequence of this defeat the Chanca deserted their former allies and made common cause with their victors. Together the armies made a determined attack on the Huanca alliance, which they broke up, and conquered the northern districts of the Chinchay-suyu. Thus Central Peru fell to the Inca arms.