James K. Polk

From 1845 to 1849, James Knox Polk (November 2, 1795 – June 15, 1849) was the 11th president of the United States. He served as Speaker of the House of Representatives from 1835 to 1839 and Governor of Tennessee from 1839 to 1841. He was a member of the Democratic Party and a proponent of Jacksonian democracy. He was a protégé of Andrew Jackson. Polk is best known for expanding the United States’ territories during the Mexican–American War; after the American victory in the Mexican–American War, the United States grew substantially with the annexation of the Republic of Texas, the Oregon Territory, and the Mexican Cession.