1. War with Mexico
Chapter 9, Section 3

2. The Annexation of Texas
Many southerners supported annexation because Texas allowed slavery
Admitting Texas to the Union as a slave state would boost the South’s political power
Other Americans had doubts about admitting Texas as a state
Concerned that US would have to bear Texas debt
Annexation would spread slavery westward
Constitution said nothing about admitting an independent nation to the US

3. The Annexation of Texas
Texas remained a republic for nine years
James K. Polk won the in 1844 and wanted annexation
Mexico warned the US that if it annexed Texas it would consider it a declaration of war against Mexico
March 1845 – Congress passed resolution annexing Texas to the United States
Texas became a part of the US on December 29,1845

4. Westward Expansion

5. Tensions between the US and Mexico
Mexico was furious about Texas annexation
Mexico still felt like Texas had been unfairly taken from it by foreigners during the Texas Revolution
Mexico broke off diplomatic relations with the US after Texas annexation

6. Polk and Manifest Destiny
March 1845 – Polk becomes president
Enthusiastic supporter of national expansion
Wanted the land between Texas and the Pacific Ocean
However, New Mexico and California belonged to Mexico
Polk thought they should become part of the US

7. The Boundary Dispute Boundary dispute between Mexico and Texas
Mexico believed it was at the Nueces River
US believed it was at the Rio Grande
Another dispute was over money
US said Mexico owed US $3 million for the loss of property and life during Mexico’s fight for independence against Spain

8. Slidell’s Trip Polk sent a special messenger to Mexico
John Slidell arrived with a US offer to cancel the $3 million claims against Mexico in exchange for Mexico’s recognition of the Rio Grande as the boundary
He was authorized to pay Mexico up to $30 million for New Mexico and California
No one would consent to meet with Slidell
He recommended to Polk that Mexico be punished

9. The Mexican-American War
Polk ordered General Zachary Taylor to advance into the disputed territory between Nueces River and Rio Grande
Led to a small skirmish
Polk used this event to request that Congress declare war on Mexico
US declared war on Mexico on May 13, 1846

10. Fighting the War General Stephen Kearny Took New Mexico quickly
California – small group of Americans revolted and forced Mexican leader to sign treaty (Became known as Bear Flag Revolt)
June 14, 1846 – Americans declared independent Republic of California (US took control about a month later)
In a matter of months, the US had control of New Mexico, California and Mexico’s capital (Mexico City)

11. Results of the War Treaty of Guadalupe Hidalgo
Ended the Mexican-American War
Mexico turned over to the US the Mexican Cession
US paid Mexico $15 million
1853 – Gadsden Purchase- clarified the treaty boundary and transferred even more land to the U.S.