The name of the lake where the Aztecs settled was Lake Texcoco. This was a lake in the Valley of Mexico. The Aztecs had migrated into the Valley of Mexico from somewhere in the north. At that time, they were not very strong. They were, however, very warlike. They became mercenaries for many of the stronger groups living in the area. However, they eventually made the king of one of these tribes very angry at them. The story is that they told the king they were going to make his daughter a goddess. Instead, they sacrificed her. At any rate, his people got extremely angry at the Aztecs and drove them away. The swampy areas around Lake Texcoco were not populated so the Aztecs hid there. After a while, Aztec legends say, they saw a sign from their gods on a small island in the lake. This sign was an eagle sitting on a cactus, holding a snake in its claws. This indicated to them that they should settle on that island. So, the Aztecs settled by Lake Texcoco.