James K. Polk

(Wikipedia) James Knox Polk (November 2, 1795 – June 15, 1849) was the 11th President of the United States (1845–49).
... When Mexico rejected the U.S. annexation of Texas (which Mexico considered part of its territory, despite the 1836 Texas Revolution), Polk led the nation to a sweeping victory in the Mexican–American War, which resulted in the cession by Mexico of nearly the whole of what is now the American Southwest. Continued