Kate E's Mexican American War Timeline By MsOlson Period: Jan 1, 1845 to Jan 1, 1849 Mexiacan Amrican War Mar 1, 1845 Texas Admitted to Union America accepts Texas into the Union under the presidency of John Tyler Mar 4, 1845 U.S. Tried to Buy Land (Sidel and Polk) Mar 4, 1846 U.S. Troops Stationed at Disputed Border May 8, 1846 U.S Victories (Battles of Palo Alto and Reseca de la Palma May 9, 1846 U.S Declares War Sep 14, 1847 Mexico City Surrendered Feb 2, 1848 Treaty of Guadelupe Hidalgo