Timeline of Events in the Mexican-American War By facebooker_100001336841030 Jan 1, 1846 President Polk Orders General Zachary Taylor to March to The Rio Grande Period: Jan 1, 1846 to Feb 2, 1848 Mexican American War Apr 25, 1846 The Thornton Affair Mexicans were taunted into war. May 3, 1846 Siege of Fort Texas May 8, 1846 Battle of Palo Alto May 9, 1846 Battle of Resaca de la Palma May 10, 1846 Decleration of War by Congress (exact date unavailable) Jul 4, 1846 Captain John C. Fremot Proclaims the Indpendence of California Jul 7, 1846 John D. Sloat takes Monterrey, California Jul 8, 1846 John D. Sloat Seizes Yerba Buena (San Fransisco) Sep 20, 1846 Battle of Monterrey Oct 7, 1846 Battle of Dominguez Rancho Nov 7, 1846 Battle of Natividad Dec 6, 1846 Battle of San Pasqual Dec 25, 1846 Battle of El Brazito Jan 2, 1847 Battle of Santa Clara Jan 8, 1847 Battle of Rio San Gabriel (Los Angeles) Jan 9, 1847 Battle of La Mesa (Los Angeles) Jan 24, 1847 Battle of La Canada Jan 24, 1847 Battle of Mora Jan 29, 1847 Battle of Embudo Pass Feb 4, 1847 Siege of Pueblo de Taos Feb 23, 1847 Battle of Buena Vista Feb 28, 1847 Battle of Sacramento Mar 9, 1847 Siege of Vera Cruz Mar 27, 1847 General Winfield Scott Captures Vera Cruz Apr 18, 1847 General Scott Drives 15,000 Mexicans From the Pass of Cerro Gordo Jun 6, 1847 Affair at Las Vegas, New Mexico Aug 19, 1847 Battles of Contreras and Churubusco Sep 8, 1847 Battle of El Molino del Rey Sep 13, 1847 Battle of Chapultepec Sep 13, 1847 Battles for the City of Mexico Sep 14, 1847 American Troops Enter the City of Mexico Oct 5, 1847 Huamantla Affair Oct 12, 1847 Siege of Puebla Oct 19, 1847 Atlixco Affair Feb 2, 1848 Treaty of Guadalupe-Hidalgo