Mexican-American War

Causes, Courses, and Consequences

Introduction

• Election of 1844James K. Polk defeated Henry Clay

• Main Goals– Oregon Question– Acquisition of California

“On to Oregon”Settling the Oregon question

• By 1840’s 5,000 Americans were in the shared territory

• British wanted everything to the 1819 Treaty line

• Americans wanted to 54°40 N, many ready to go to war “54 40 or fight”

• Compromised on 49°N

Acquisition of California

• Many Americans wanted more direct trade with Asia

• Manifest Destiny• Polk was willing to buy California from Mexico

Causes of the Mexican American War

• Annexation of Texas– Many hesitant to Annex Texas• Feared war with Mexico• Feared the expansion of slavery• The constitutionality of annexation was unclear• Soon after election of Polk on an expansionist program

bill passed by Congress to accept Texas

• Provocations by United States• General Taylor sent to establish a base in the disputed

area between the Nueces and Rio Grande Rivers to defend Texas from invasion by the Mexicans and invade Texas if necessary• When Mexico refused to sell New Mexico, settle border

dispute Taylor was ordered into the disputed region• Naval squadron in the Pacific ordered to invade

California ports if war broke out

Course of Events

• 1846– Americans campaign in northern Mexico captures

Monterey– Troops leave Fort Leavenworth in Kansas to

capture Santa Fe and then on to California– Pacific Naval Squadron captures California coastal

towns with the help of American settlers

• 1847– American troops under Winfield Scott capture

Tampico , Vera Cruz and then march on and capture Mexico City

Treaty of Guadalupe Hidalgo

• February 1848• Mexico ceded California, Nevada, Arizona, New

Mexico and Utah• Mexico recognized Texas as American territory as

far south as the Rio Grande• United States withdrew all troops from Mexico• United States paid Mexico 15 million• United States assumed U.S. citizen claims against

Mexico

Effects of the Mexican-American War

• Huge acquisition of land• Permanent borders with British Canada and

Mexico• United States stretches from Atlantic to Pacific

Coast

Summing Up

• Causes• Course• Effects