James Gadsden (1788-1858), American railroad promoter and a leading advocate of Southern nationalism, was the minister to Mexico responsible for the Gadsden Purchase in 1853.

James Gadsden was born in Charleston, S.C., on May 15, 1788, the grandson of a Revolutionary patriot. After graduating from Yale College in 1806, Gadsden entered business and then became a professional army officer, rising to the rank of colonel by 1820. During the War of 1812 he served as an engineer and as an aide to Gen. Andrew Jackson. Later he fought against the Seminole Indians and was responsible for securing the evidence which led to the seizure, trial, and execution of two British agents.

In 1821 Gadsden served as adjutant general, but the Senate refused to confirm his appointment. Gadsden resigned from the Army and moved to Florida, where he was active in the territory's affairs. In 1823 he was responsible for placing the Seminoles on reservations and...