Mexican-American War

Definition

The Mexican-American War was a conflict between the United States and Mexico from 1846 to 1848, primarily driven by the U.S. expansionist ideology known as Manifest Destiny. The war resulted in significant territorial gains for the United States, including present-day California, Arizona, New Mexico, and parts of Colorado, Utah, and Nevada, fundamentally altering the landscape of North America and intensifying debates over slavery in the newly acquired territories.

5 Must Know Facts For Your Next Test

1. The war began after a series of border disputes following the U.S. annexation of Texas, which Mexico still considered part of its territory.
2. U.S. President James K. Polk was a strong proponent of Manifest Destiny and played a key role in escalating tensions that led to the war.
3. The conflict was marked by several key battles, including those at Palo Alto, Buena Vista, and Mexico City, showcasing American military superiority.
4. As a result of the war, the United States acquired over 500,000 square miles of territory, significantly increasing its size and resources.
5. The Mexican-American War intensified sectional conflicts over slavery, as debates emerged about whether new territories would be free or slave states.

Review Questions

• How did the belief in Manifest Destiny contribute to the outbreak of the Mexican-American War?
  • The belief in Manifest Destiny played a crucial role in the outbreak of the Mexican-American War by fostering a sense of American entitlement to expand its territory across North America. This ideology convinced many that it was their duty to spread democracy and civilization, leading to aggressive actions such as the annexation of Texas. The desire for expansion into Mexican territories heightened tensions and set the stage for conflict.
• Analyze the significance of the Treaty of Guadalupe Hidalgo in shaping U.S.-Mexico relations after the war.
  • The Treaty of Guadalupe Hidalgo was significant because it not only formally ended the Mexican-American War but also redrew borders between the U.S. and Mexico, resulting in substantial territorial losses for Mexico. The treaty ceded vast lands to the United States, fundamentally altering the geopolitical landscape in North America. It laid a foundation for future U.S.-Mexico relations and sowed seeds of resentment in Mexico that lingered for generations.
• Evaluate how the outcomes of the Mexican-American War influenced domestic politics in the United States regarding slavery.
  • The outcomes of the Mexican-American War had profound effects on domestic politics in the United States by intensifying debates over slavery as new territories were added. The question arose whether these territories would permit slavery or not, leading to fierce political battles like those surrounding the Wilmot Proviso and later contributing to sectional tensions that ultimately culminated in the Civil War. The war thus not only expanded U.S. territory but also deepened divides within American society.

Related terms

Treaty of Guadalupe Hidalgo:

The treaty that ended the Mexican-American War in 1848, leading to the cession of a large portion of Mexico's northern territories to the United States.

Manifest Destiny:

The 19th-century belief that American settlers were destined to expand across North America, justifying territorial expansion and often leading to conflicts with other nations.

Bear Flag Revolt: A rebellion by American settlers in California against Mexican rule in 1846, which contributed to the U.S. annexation of California during the Mexican-American War.