Mexican War
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Events leading up to the Mexican American War

It followed in the wake of the 1845 U.S. annexation of Texas, which Mexico considered part of its territory, despite the 1836 Texas Revolution, which included the Battle of the Alamo.

1821: Mexico attains independence from Spain

1836 Texas Revolution

Mexico: Mexico refusal to recognize the independence of Texas and President Polk's support of Manifest Destiny was set on a collision path.


"The Mexican Government refused to accept Texas' Independence even after Santa Anna signed the Treaty of Velasco at San Jacinto." (Source: P. L. Buquor, Indian Fighter, Texas Ranger, Mayor of San Antonio",  By Sylvia Villarreal Bisnar, p. 63)

1845 US annexation of Texas

1848 The Treaty of Guadalupe Hidalgo

The land ceded to the United States, by the Treaty of Guadalupe Hidalgo, became all or part of ten states: Texas (1845),California (1850), Kansas (1861), Nevada (1864), Colorado (1876), Wyoming (1890), Utah (1896), Oklahoma (1907) and New Mexico (6, Jan,1912) and Arizona (14, Feb,1912).

National Sites

Mexican War Veterans: A Complete Roster of the Regular and Volunteer Troops, By William Hugh Robarts

A Continent Divided



Texas online


The Occupation of Mexico May 1846- July 1848


California during the Mexican American War

Missions, Ranchos, and the Mexican War for Independence

Treaty of Guadalupe Hidalgo


Background for headings: "Nebel Mexican War 02 Capture of Monterrey" by Adolphe Jean-Baptiste Bayot - Immediate image source: Link

             Originally published in George Wilkins Kendall & Carl Nebel: The War between the United States and Mexico Illustrated, Embracing Pictorial Drawings of all the Principal Conflicts, New York: D. Appleton; Philadelphia: George Appleton [Paris: Plon Brothers], 1851.. Licensed under Public domain via Wikimedia Commons - Link