After the French and Indian War, France ceded all of the Louisiana Purchase west of the Mississippi River and the territory of New Orleans to Spain and ceded the Florida Parishes (also known as Spanish West Florida) to England. Thus, Baton Rouge became an important military outpost for the southwest corner of the British Empire in North America. The British promptly renamed Baton Rouge "Fort New Richmond", which it stayed until September 1779 when Spanish territorial governor Don Bernardo de Galvez captured New Richmond and named it Fort San Carlos. When Napoleon sold Louisiana to the United States in 1803, the fort remained in the possession of Spain, becoming the only port on the entire Mississippi River that did not belong to the US. In 1810, Fort San Carlos' citizens revolted, and overthrew Spanish rule, and renamed the town Baton Rouge, and claimed it the capital of the West Florida Republic.