The treaty that ended the Mexican-American War was the Treaty of Guadalupe Hidalgo, signed on February 2, 1848. This treaty resulted from the United States' victory in the war, which began in 1846 primarily over territorial disputes involving Texas. The treaty ceded vast territories, including present-day California, Arizona, New Mexico, Nevada, Utah, and parts of Colorado and Wyoming, to the U.S. In exchange, the U.S. paid Mexico $15 million and assumed certain claims of American citizens against Mexico. The treaty significantly expanded U.S. territory, shaping the nation's future and intensifying debates over slavery in the newly acquired lands.