Jonathan L's Mexican American War Timeline By MsOlson Period: Jan 1, 1845 to Jan 1, 1849 Mexican American war Mar 1, 1845 Texas admitted to the Union President John Tyler signs Congressional Resolution to add Texas Nov 1, 1845 US Tried to Buy Land (Sidel and Polk) John Sidell is sent to Mexico by Polk to try and purchase New Mexico and Califonia Mar 1, 1846 US Troops Stationed at Disputed Border General Taylor's army moves past the Nueces River and into the disputed land claimbed by both the U.S. and Mexico May 1, 1846 US Declares War Polk asks Congress to delcare war on Mexico. Congress agrees and delcares war on Mexico. Congress approves $10 million and 50,000 volentees. Sep 23, 1846 U.S. victory General Taylor, with 6,640 men, attack the City of Monterry. General Ampudia, with 5,000 men defends the city, but was eventually defeated. Sep 13, 1847 Mexico City Surrendered After 14 days of American shelling, Mexico City surrenders to U.S. forces. U.S> forces then occupy Mexico City. Feb 2, 1848 Treaty of Guadelupe Hidalgo Negotiators agree on the Treaty of Guadalupe Hidalgo. The Treaty is rushed to Washington. Among other things the Treaty of Guadelupe Hidalgo causes Mexico to lose 55% of its land.