Mexican-American War & Western Expansion
Florida
– Adams-Onis (Transcontinental) Treaty of 1819 Florida Cession
– U.S. gained the Florida Territory - Spain withdrew from Oregon Territory- The U.S. gave up
Texas
Stephen F. Austin
– American who moved to Texas in 1822
– Encouraged other Americans to move to the territory
– He is considered the “Father of Texas”
Texas Revolution
1. American Settle in Texas
– Texas was part of Mexico
– US settlers had to give up US citizenship
– These settlers were still loyal to US
– Americans who just happened to live in Mexico
2. Tensions in Texas
– Mexico tried to strengthen their authority in Texas
– Banned US immigration into Texas
– Sent troops in to enforce this
3. Revolution
– Tensions grow between Texans and Mexico
– Battles break out in October 1835
– Texans lose at the Alamo
– 1836 Texas Declares independence
– Texans defeat Mexican troops and sign treaty ending war
– Texas becomes independent (Republic of Texas)
Causes of Mexican-American War
1. Annexation of Texas
– Texas wants to become a US state
– Mexico warns US allowing this to happen will be an act of war
– March 1845: US annexes (takes control of) Texas
– Becomes part of US in Dec. 1845
– Mexico breaks diplomatic relations with the US
2. Manifest Destiny
– View that the US was ordained by God to control the land all the way to the Pacific Ocean
– President Polk wanted control of the land from Texas to the Pacific Ocean
– Mexico controlled this land
3. Boundary Disputes
– Mexico: Border is Nueces River
– Texas: Border is Rio Grande River
– When Texas was annexed US claims the border as the Rio Grande
The War
1. Polk Ignites a War
– President Polk sends troops into the disputed territory
– Hoped a battle would break out in order to declare war
– Small fight breaks out in territory
– Polk uses this incident to request war
– Says that Mexicans: “invaded our territory and shed the blood of our fellow citizens on our
own soil.”
2. Fighting the War
– US uses an aggressive strategy to fight war
– Troops capture Santa Fe and take over NM territory
– Americans in California revolt (Bear Flag Revolt) and declare independence
– US takes control of CA
– US invades at Gulf of Mexico and captures the Capital
Results of the War
1. Treaty of Guadalupe Hidalgo
– Signed in 1848
– Ends war
– Mexico must turn over land to the US
– Mexico acknowledging the Rio Grande as the border.
2. Mexican Cession
– Land Mexico turned over
– AZ, CA, UT and parts of CO, NM, and WY
– US gave Mexico $15 million
3. Gadsden Purchase (1853)
– Clears up boundary issues
– Gives more land to the US
– Southern AZ and NM
– US was supposed to pay $10 million, only gave $7 million, $6 million reached the Mexican
Government
Oregon Country
– President Polk wanted control of the Oregon Territory and was willing to go to war with
Britain. “54º40' or fight” was his position. The Oregon dispute was settled peacefully on
the 49° in the Treaty of Oregon in 1846.
Alaska
– In 1867, Secretary of State William Seward purchased Alaska from Russia for $7.2
million
• Critics mocked “Seward’s Icebox” and “Seward’s Folly” as a far off and useless
frozen tundra.
• But, valuable resources including gold, timber, and oil were found.
• Alaska also doubled America’s territory.