The little village of Guadalupe Hidalgo near Mexico City was the site of the signing of the treaty that ended the
Mexican American War. The treaty required Mexico to give up all the territory that President
James K. Polk had demanded from the outset: the Rio Grande region, New Mexico and California. The United States paid Mexico $15,000,000 for the territory. The territory thus acquired added 525,000 square miles to the territory of the United States. Later in 1853, the
Gadsden Purchase added another 29,640. An unanticipated result of these acquisitions was the reopening of controversies over slavery. The question of whether the new territories should be free or slave agitated the country until the
Civil War.
