Mexican-American War

I

Introduction

Mexican-American War (1846-1848), conflict between the United States and Mexico. The war resulted in a decisive US victory and forced Mexico to relinquish all claims to approximately half its national territory.

II

The Road to War

The causes of the Mexican-American War lay in the continued westward expansion of the United States into land claimed by Mexico, and the inability of the newly independent Mexican government to control its most northerly areas. Specifically, the Fredonian Rebellion in 1826, the Texas Revolution in 1835, and the annexation of Texas by the United States in 1845 led to a rapid deterioration in relations between the two countries.

A

The Fredonian Revolution

In 1825 a group of Texas colonists received permission from the Mexican government to colonize an area in eastern Texas known as Nacogdoches. By the time they arrived, however, other settlers had already claimed the region. The Texas colonists threatened to expel anyone who could not produce a valid land title. After the original settlers protested, the Mexican government denied the Texans permission to colonize the region.

In December 1826 a group of 16 Texas colonists went to Nacogdoches and proclaimed the region to be the independent Republic of Fredonia. The next month about 60 men, mostly Mexicans, rode to Nacogdoches to capture the rebellious Fredonians. The small garrison of Fredonians soundly defeated their attackers in the only battle of the rebellion. When Mexican troops arrived at Nacogdoches a short time later, the republic had been dissolved and the leader of the colonists had fled to Louisiana.

B

The Texas Revolution

Although the Fredonians were not successful, by the 1830s the population of Mexican Texas included many immigrants from the United States. These Anglo-American colonists were angry over Mexican attempts to deny autonomy to Texas and were unhappy with a colonization law that prevented immigration from the United States into Texas. They were also wary of the Catholic laws and customs of the Mexicans. In 1835 they revolted and established Texas as an independent republic. The Texas Revolution included the battles of The Alamo, Goliad, and San Jacinto. When hostilities ceased, the Mexican general Antonio López de Santa Anna agreed to withdraw his troops across the Río Grande and recognize the independence of Texas. The Mexican congress rejected the agreement, and many Mexicans assumed the nation would regain Texas. It soon became apparent, however, that Mexico was in no position to retake Texas by force. Texas remained independent from 1836 to 1845, when the United States Congress approved a joint resolution annexing Texas. Mexico considered this annexation an act of aggression, and the Mexican ambassador in Washington, D.C., broke off negotiations and went home.