The orgins of the Aztec are uncertain. Sometime during the twelfth century A.D., they established a capital at Tenochtitlan, now Mexico City. There they would rule until the spanish conquest. In 1325, under attack by another people, they were driven into swampsand islands of Lake Texeoco. By 1500, as many as four million Aztec lived in the Valley of Mexico and the surrounding valleys of central Mexico. The Aztecs also believed in many Gods.