James K. Polk (1795-1849) was the 11th President of the United States, serving from 1845 to 1849. Born in North Carolina, he was a prominent figure in American politics, having also served as Speaker of the House of Representatives and Governor of Tennessee. Polk's presidency was marked by territorial expansion, including the annexation of Texas, the Oregon Territory, and the acquisition of California and the Southwest from Mexico through the Mexican-American War. He was known for his strong leadership and ambitious vision for the nation, making him one of the most influential presidents in U.S. history.