On this day, the United States buttresses its control over the Gadsden Purchase with the establishment of Fort Buchanan. Named for recently elected President James Buchanan, Fort Buchanan was located on the Sonoita River in present-day southern Arizona.
The U.S. acquired the bulk of the southwestern corner of the nation from Mexico in 1848 as victors’ spoil after the Mexican War. However, congressional leaders, eager to begin construction of a southern railroad, wished to push the border farther to the south. The government directed the American minister to Mexico, James Gadsden, to negotiate the purchase of an additional 29,000 square miles.
Despite having been badly beaten in war only five years earlier and forced to cede huge tracts of land to the victorious Americans, the Mexican ruler Santa Ana was eager to do business with the U.S. Having only recently regained power, Santa Ana was in danger of losing office unless he could quickly find funds to replenish his nearly bankrupt nation. Gadsden and Santa Ana agreed that the narrow strip of southwestern desert land was worth $10 million. When the treaty was signed on December 30, 1853, it became the last addition of territory (aside from the purchase of Alaska in 1867) to the continental United States. The purchase completed the modern-day boundaries of the American West.
The government established Fort Buchanan to protect emigrants traveling through the new territory from the Apache Indians, who were strongly resisting Anglo incursions. However, the government was never able to fulfill its original purpose for buying the land and establishing the fort—a southern transcontinental railroad. With the outbreak of the Civil War four years later, northern politicians abandoned the idea of a southern line in favor of a northern route that eventually became the Union Pacific line.