Handsome, intelligent and capable, John Charles Fremont acquired valuable navigational and mapping skills while still in his twenties, as a member of the Army Topographical Corps’ exploration of the immense northern sections of the Louisiana Purchase— today the northern Midwest. In 1842 He was commissioned to survey and map the newly established Oregon Trail as far as South Pass, and the following year he was assigned to lead another exploration of the Pacific Northwest. In and out of California throughout 1844-1846, Fremont encouraged and advised the rebels who instigated the Bear Flag Revolt in June 1846, although as an Army officer he remained behind the scenes until he decided to go on the offensive by creating the California Battalion. Three weeks later American warships arrived, to protect California upon declaration of the Mexican-American War. Afterwards, Fremont was court-martialed on charges of mutiny, disobedience and unlawful conduct. Pardoned in part by President Polk, Fremont nonetheless resigned his commission and returned to California with his wife and family. Fremont is the man who named the Golden Gate, and his detailed reports and accurate maps inspired thousands to emigrate to the Pacific Coast regions. He was briefly one of two U.S. Senators from California, ran for president of the United States in 1855, and served as a general during the Civil War until unwise decisions led to his being relieved of command. He died in 1890. By turns celebrated and reviled in his own lifetime, John Fremont remains a controversial figure in California’s history.