Mexican-American War Books

About Mexican-American War

The Mexican-American War (1846–1848) was a pivotal conflict between the United States and Mexico that reshaped the map of North America. Rooted in territorial disputes and driven by the U.S. doctrine of Manifest Destiny—the belief that the U.S. was destined to expand across the continent—the war began after the U.S. annexed Texas, which had previously won independence from Mexico. Mexico refused to recognize the annexation and border tensions escalated. When U.S. troops were attacked in disputed territory near the Rio Grande, Congress declared war. The war featured major battles at Palo Alto, Monterrey, Buena Vista, and the siege of Veracruz, culminating in the capture of Mexico City in 1847. U.S. generals like Zachary Taylor and Winfield Scott gained national fame, and future Civil War leaders such as Ulysses S. Grant and Robert E. Lee saw early service. The Treaty of Guadalupe Hidalgo ended the war in 1848, forcing Mexico to cede vast territory—present-day California, Arizona, New Mexico, Nevada, Utah, and parts of several other states—in exchange for $15 million. The war was controversial in the U.S., fueling tensions over the expansion of slavery and contributing to the sectional divide that would lead to the Civil War. For Mexico, the war was a national trauma, marking a significant loss of land and prestige. It also altered the power dynamics in the Americas and laid the groundwork for westward expansion and internal conflict in the United States.