Knowing the Presidents: James K. Polk

James K. Polk

Eleventh President, 1845-1849


In 1844, James K. Polk became the first dark horse candidate to win the presidency, beating Henry Clay.

Polk promised that he would be a one-term president.


James K. Polk was an avowed expansionist, committed to acquiring California and New Mexico from Mexico even at the risk of war.

Polk acquired the then British-held territory of Oregon and negotiated for its border to be located along the 49th parallel.

Major Acts:

Congress declared war with Mexico in 1846.

In 1848, Mexico ceded California, Nevada, Arizona, Utah, and parts of Wyoming, Colorado, and New Mexico—more than fifty percent of Mexico at the time—to the U.S. for fifteen million dollars.


During James K. Polk’s four years in office, the nation acquired vast lands that expanded the country to reach across the continent to the Pacific Ocean.

Polk was a tireless achiever and left the White House in a state of exhaustion. He died four months later.