John Charles Frémont

Frémont, John Charles (1813–90), U.S. explorer, general, politician, and popular hero. He mapped much of the territory between the Mississippi valley and the Pacific during the early 1840s. He was caught up in the struggle with Mexico over California, being appointed military governor but later convicted of mutiny (1847–48), a sentence commuted by President James Polk. Frémont stood as the Republican Party's first presidential candidate (1856) but was defeated by James Buchanan. He had to resign as commander of the Department of the West during the Civil War for exceeding his office by declaring martial law. He was governor of Arizona territory 1878–83.