river and the Pachachaca, submitted at once. It was the land of the Quichuas, very closely allied to the Incas. The next region, between the river Pachachaca and the Pampas, containing the beautiful valley of Andahuaylas, the chief seat of the Chancas, also submitted. The Chancas even added an important contingent to the Inca army. Beyond the Pampas, the Soras and Lucanas, hardy mountaineers, submitted after a brief struggle. These were the first fruits of the victory over the Chancas. Pachacuti next invaded the basin of Lake Titicaca, and the whole region was annexed after three hard- fought campaigns against the Collas.
Then followed a campaign during which the whole northern region of the Andes, as far as Caxamarca, was added to the empire.
By this time Pachacuti was well stricken in years. His eldest son was Amaru Tupac, a very able and successful general, who was, at one time, intended to be his heir. But the question of the succession was a very important one, and something more was needed than a successful general. By his wife Anahuarqui, the Inca had another son, also named Tupac, in whom the great statesman saw the germs of such genius as would fit him to succeed to the responsibility of guiding an empire. After an interview with his father, the eldest son, Amaru, accepted the situation and remained loyal to his younger brother until death. Young Tupac went through the ceremony of being armed, and then proceeded on a great
