The treaty that ended the Mexican-American War in 1848, resulting in significant territorial gains for the U.S., is the Treaty of Guadalupe Hidalgo. This treaty concluded hostilities between the two nations and ceded a large portion of Mexico's northern territories to the United States, including present-day California, Arizona, New Mexico, and parts of Colorado, Utah, and Nevada. This acquisition expanded U.S. territory significantly and fulfilled the idea of Manifest Destiny, but also intensified debates over slavery in the newly acquired lands.