Signifigance of the Topic


These activities focus on the various perspectives involved with the Mexican-American War. Students develop an understanding of "Manifest Destiny" and how it influenced the westward movement. Students will understand how the continued migration of Mexican settlers and American settlers led to the disagreement of where each country's borders existed. Students will be able to explain how and when the various lands of the west became part of the United States. They will be able to relate the significance of the Texas War for Independence and the Mexican-American War.

Historical Context:

Mexico had gained independence in 1824. The constitution provided a federal republic, 19 states, 4 territories, and a federal district. Their government was divided by two factions; the Centralists who favored a strong central government with a vice-regal tradition and the Federalists, who favored limited central government, local militia, and nearly autonomous states. The pendulum of power swept back and forth.

The United States was moving west and following what was thought to be its Manifest Destiny (The belief that it was the destiny of the United States to occupy all of North America). American settlers (30,000 immigrants) had moved into Texas with the permission and encouragement of the Mexican Government. The growing numbers caused fear in the Mexican Government and they closed the borders. With the adoption of a new Mexican Constitution the Texan settlers were disenfranchised and faced the elimination of all vestiges of states' rights. Texas declared itself an independent republic.

Santa Anna was the president of Mexico during these growing tensions. He gathered an army to crush the revolt. He led these soldiers himself and successfully captured the Alamo. Later he was defeated and captured by the Texas forces in April 1836. The United States annexed Texas in 1845 which caused Mexico to terminate diplomatic relations. The United States claimed the territory to the Rio Grande River but Mexico claimed it only extended to the Nueces River.

Under the new administration of James K. Polk, the United States tried to purchase the disputed territory, but Mexico refused. President Polk ordered U.S. soldiers to occupy the territory between the two rivers. This led to the battle at Buena Vista which was lost by Santa Anna and his troops. Because of the shed blood the two countries felt they had no course to take but war. Various battles occurred over the next year and the United State invaded Mexico and captured Mexico City on September 14, 1847.

Dated February 2, 1848, the Treaty of Guadalupe Hidalgo terminated the war. Under its terms Mexico ceded all territory north of the irregular line of the Rio Grande and the Gila River across the Colorado to the Pacific. The United States paid Mexico $15,000,000 and assumed $3,250,000 in claims held by U.S. citizens against Mexico.

By December of 1853 the conservatives had taken control of the Mexican government and Santa Anna had declared himself dictator. To raise funds for an expanded army to defend his government and power, Santa Anna sold the territory south of the Gila River to the United States for $10,000,000. Known as the Gadsden Purchase, it is the boundary we recognize between Mexico and the United States.

Essential Questions to be addressed:

  1. How does Expansion affect the people involved?
  2. Are the effects of Expansion always positive?
  3. How does Expansion effect the values of lives?
  4. How do the people involved in Expansion differ from those already in the area?

Outcome Questions:

  1. How did the idea of "Manifest Destiny" contribute to the Mexican American War?
  2. How did the changes in Mexico's government contribute to the Mexican American War?
  3. How did the annexation of the Republic of Texas effect relations between Mexico and the United States?
  4. What were the important outcomes of the Treaty of Guadalupe Hidalgo and the Gadsden Purchase?

Signifigance of the Topic
Student Activities
Teaching Strategies
Standards Addressed
Extensions across the Curriculum