Mexican-American War By sridge Mar 2, 1836 Texas declares independence from Mexico Apr 21, 1836 Texas becomes an independent nation Nov 1, 1839 John L. O'Sullivan published his paper on Manifest Destiny Aug 1, 1843 Mexican General Santa Anna threatens U.S. with war if Texas is annexed Jan 1, 1844 54-40 or Fight Feb 28, 1845 U.S. Congress passes bill for annexation of Texas Mar 1, 1845 President John Tyler signed the bill for the annexation of Texas / Mexico and U.S. end diplomatic relations Mar 4, 1845 James K. Polk becomes President Jun 25, 1845 Polk sends General Zachary Taylor to protect Texas from Mexican invasion Oct 13, 1845 Texas Republic votes to become part of the U.S. Oct 13, 1845 The U.S. government asked the Mexican government if they would permit an envoy to "adjust all the questions in dispute between the two Governments." Oct 15, 1845 The Mexican minister requested an envoy and asked the naval force at Vera Cruz be removed Nov 10, 1845 John Slidell was sent to Mexico with an envoy to establish the location of the Texas boundary. Dec 10, 1845 John C. Frémont entered California with a small armed force Dec 21, 1845 Mexican minister refused Slidell's offer Dec 29, 1845 Annexation of Texas and Texas becomes 28th state in U.S. Apr 25, 1846 Thornton Affair May 11, 1846 Polk encouraged Congress to declare War Congress conferred for a few hours and the decision was quickly made to declare war on Mexico. May 13, 1846 Congress declared war on Mexico Jun 14, 1846 Bear Flag Revolt begins in California Jul 7, 1846 Mexican Congress declares war on U.S.
