One of the tribes that moved into the Valley of Mexico in the 14th century were the Mexica, at a time when the city of Culhuacán was powerful. However, the area was divided into a number of dominions around the lake system of the valley, which vied among themselves for dominance. As late arrivals, the Mexica wandered among the various dominions and were granted permission to settle in Culhuacán territory. They lived together mostly peacefully. However, records indicate that the Mexicas were forced into servitude as punishment for raids by young warriors to carry off women from neighboring settlements. One legend states that problems between the two peoples began when the Mexica asked for and received a Culhua princess, Achitómetla, to become a goddess of war. The ceremony required the woman to be sacrificed, angering Culhuacán. The Mexica were eventually forced off Culhua lands and forced to settle on an island on the west side of the lake, although the stronger city of Culhuacán maintained relations with them. This new settlement, called Tenochtitlan, would begin rising and dominating since its establishment in 1325. The Aztec Triple Alliance would be formed in the early 15th century, as part of the process of uniting the Nahuatl-speaking peoples of the valley.