Original sentence: It is represented as a volcano in a lake, located in what is now the north of Mexico (including the territory from Texas to California annexed by the United States after the Mexican-American War), onto which the first Mexica emerged at the beginning of the fourth world.These stories helped fuel Spanish expeditions to what are now the Southwestern states of the United States
Edited sentence: It is represented as a volcano in a lake, located in what is now the north of Mexico (including the territory from Texas to California occupied by the United States), onto which the first Mexica emerged at the beginning of the fourth world.These stories helped fuel Spanish expeditions to what is now the Southwestern states occupied by the United States