Humanities › History & Culture James K. Polk, 11th President of the United States Share Flipboard Email Print Hulton Archive/Stringer/Getty Images History & Culture American History U.S. Presidents Basics Important Historical Figures Key Events Native American History American Revolution America Moves Westward The Gilded Age Crimes & Disasters The Most Important Inventions of the Industrial Revolution African American History African History Ancient History and Culture Asian History European History Genealogy Inventions Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By Martin Kelly History Expert M.A., History, University of Florida B.A., History, University of Florida Martin Kelly, M.A., is a history teacher and curriculum developer. He is the author of "The Everything American Presidents Book" and "Colonial Life: Government." our editorial process Martin Kelly Updated June 28, 2019 James K. Polk was president during the Mexican American War and the era of Manifest Destiny. Learn more about the 11th president of the United States. James K. Polk's Childhood and Education James K. Polk was born on November 2, 1795, in Mecklenburg County, North Carolina. He moved with his family at the age of ten to Tennessee. He was a sickly youth who suffered from gallstones. Polk did not begin his formal education until 1813 at the age of 18. By 1816, he entered the University of North Carolina and graduated with honors in 1818. He decided to enter politics and also was admitted to the bar. Family Ties Polk's father was Samuel, a planter and landowner who was also a friend of Andrew Jackson. His mother was Jane Knox. They had been married on Christmas Day in 1794. His mother was a staunch Presbyterian. He had five brothers and four sisters, many of whom died young. On January 1, 1824, Polk married Sarah Childress. She was well-educated and wealthy. While first lady, she banned dancing and liquor from the White House. Together, they had no children. James K. Polk's Career Before the Presidency Polk had focused on politics his whole life. He was a member of the Tennessee House of Representatives (1823-25). From 1825-39, he was a member of the U.S. House of Representatives including serving as its speaker from 1835-39. He was a great ally and supporter of Andrew Jackson. From 1839-41, Polk became Governor of Tennessee. Becoming President In 1844, the Democrats were having a difficult time getting the necessary 2/3 of the vote to nominate a candidate. On the 9th ballot, James K. Polk who had only been considered as a Vice Presidential candidate was nominated. He was the first dark-horse nominee. He was opposed by Whig candidate Henry Clay. The campaign centered around the idea of annexation of Texas which Polk supported and Clay opposed. Polk received 50% of the popular vote and won 170 out of 275 electoral votes. Events and Accomplishments as President James K. Polk's time in office was eventful. In 1846, he agreed to fix the boundary of the Oregon territory at the 49th parallel. Great Britain and the United States disagreed about who claimed the territory. The Oregon Treaty meant that Washington and Oregon would be a territory of the U.S. and Vancouver would belong to Great Britain. Much of Polk's time in office was taken up with the Mexican War which lasted from 1846-1848. The annexation of Texas which had taken place at the end of John Tyler's time in office hurt relations between Mexico and America. Further, the border between the two countries was still disputed. The U.S. felt that the border should be set at the Rio Grande River. When Mexico would not agree, Polk prepared for war. He ordered General Zachary Taylor to the area. In April 1846, Mexican troops fired on the U.S. troops in the area. Polk used this to push forward a Declaration of War against Mexico. In February 1847, Taylor was able to defeat the Mexican army led by Santa Anna. By March 1847, U.S. troops occupied Mexico City. Concurrently in January 1847, Mexican troops were defeated in California. In February 1848, the Treaty of Guadalupe Hidalgo was signed ending the war. By this treaty, the border was fixed at the Rio Grande. By this means, the U.S. gained California and Nevada amongst other present-day territories amounting to over 500,000 square miles of land. In exchange, the U.S. agreed to pay Mexico $15 million for the territory. This agreement reduced the size of Mexico to half of its former size. Post Presidential Period Polk had announced before taking office that he would not seek a second term. He did retire at the end of his term. However, he did not live much past that date. He died only three months later, possibly from Cholera. Historical Significance After Thomas Jefferson, James K. Polk increased the size of the United States more than any other president through the acquisition of California and New Mexico as a result of the Mexican-American War. He also claimed Oregon Territory after a treaty with England. He was a key figure in Manifest Destiny. He was also an extremely effective leader during the Mexican-American War. He is considered to be the best one-term president.