Polk was the 11th president of the United States, serving from 1845 to 1849.

James Knox Polk was born on November 2, 1795, in a log cabin in Pineville, North Carolina. He was the first of 10 children born into a family of farmers. His mother Jane named him after her father, James Knox.

During his 1824 campaign for Tennessee's 6th congressional district, Polk's opponents said that at the age of 29 he was too young for the responsibility of a seat in the House, but Polk won the election with 3,669 votes out of 10,440 and took his seat in Congress on March 4, 1825.

He left Congress to run for governor of Tennessee, winning in 1839, but losing reelection bids in 1841 and 1843. Polk's three major programs during his governorship--regulating state banks, implementing state internal improvements, and improving education--all failed to win the approval of the legislature.

During Polk's political career, Sarah Childress Polk assisted her husband with his speeches, gave him advice on policy matters, and played an active role in his campaigns. Polk biographer James A. Rawley noted that Sarah Polk's grace, intelligence and charming conversation helped compensate for her husband's often austere manner.

A protégé of Andrew Jackson, he was a member of the Democratic Party and an advocate of Jacksonian democracy.

He was a dark horse candidate for the Democratic nomination for president in 1844. He entered his party's convention as a potential nominee for vice president, but emerged as a compromise to head the ticket when no presidential candidate could secure the necessary two-thirds majority. In the general election, Polk defeated Henry Clay of the rival Whig Party.

Polk achieved a sweeping victory in the Mexican-American War, which resulted in the cession by Mexico of nearly all the American Southwest, including California, Nevada, Utah, and most of Arizona.

A devout Presbyterian, First Lady Sarah Childress Polk banned dancing, card games, and hard liquor at official receptions. Unlike Julia Tyler's waltzes, the Polk entertainments were sedate and sober affairs which earned the First Lady the nickname "Sahara Sarah".

Polk vetoed three bills during his presidency (2 regular vetoes and 1 pocket veto), including the Rivers and Harbors Bill in 1846, which would have provided $500,000 to improve port facilities.