The Treaty of Guadalupe Hidalgo, signed on February 2, 1848, marked the end of the Mexican-American War, which had begun in 1846. Under this treaty, Mexico ceded approximately half of its territory, including present-day California, Arizona, New Mexico, and parts of Colorado, Utah, and Nevada, to the United States. This significant territorial expansion fueled debates over slavery in the new territories and set the stage for future conflicts, including the Civil War.

The Treaty of Guadalupe Hidalgo not only reshaped the U.S.-Mexico border but also gave rise to Chicano literature, with poets like José Montoya and Sandra Cisneros exploring themes of identity, displacement, and cultural heritage. This treaty's legacy is reflected in the rich tapestry of border narratives that continue to influence contemporary poetry.