James Gadsden was an American diplomat and soldier, best known for his role in the Gadsden Purchase of 1854. Born on June 15, 1788, in South Carolina, he served in the U.S. Army during the War of 1812 and later became a prominent figure in the expansionist policies of the United States. The Gadsden Purchase involved the acquisition of land from Mexico that is now part of Arizona and New Mexico. This purchase aimed to facilitate a southern transcontinental railroad and was significant in shaping the borders of the United States. Gadsden's efforts in this negotiation reflect the broader themes of American expansion during the 19th century.