James Knox Polk was the 11th president of the United States and a protege (one whose career is helped by the influence of another) of Andrew Jackson, who was a good friend of the prosperous farming Polk family in Tennessee.
Polk was too sick as a child to get formal schooling, yet managed to graduate at the top of his class from the University of North Carolina when he was 22. He was nicknamed "Napoleon of the Stump" for his excellent speaking skills. Polk was a very hard-working chief executive who proved to be one of the most productive presidents in history. He greatly expanded the U.S. territory and reestablished the independent treasury system, among many other accomplishments.
Upon election, he vowed to serve only one term, a promise he kept when he declined to run in 1848.