U.S. History / Unit 3: The Early Republic and Expansion
3.6 Manifest Destiny and Westward Expansion
Notes
Manifest Destiny was the belief, named in 1845, that the United States was destined to spread across the continent.
- Texas won independence from Mexico in 1836 (the Alamo, San Jacinto) and was annexed by the U.S. in 1845.
- Oregon was split with Britain at the 49th parallel (1846). Settlers traveled the Oregon Trail.
- Mexican-American War (1846 to 1848): began after a border dispute in Texas. Some, like Abraham Lincoln and Henry David Thoreau, opposed it as a land grab.
- The Treaty of Guadalupe Hidalgo (1848) gave the U.S. the Mexican Cession, including California and much of the Southwest.
- The California Gold Rush (1848 to 1849) brought a flood of settlers; California became a state in 1850.
- Expansion displaced Native nations and Mexican residents and reopened the fight over slavery in new territories.
Practice
Manifest Destiny was the belief that:
Supporters saw continental expansion as natural and inevitable.
Which land did the United States gain from the Treaty of Guadalupe Hidalgo?
Mexico ceded about half of its territory, the Mexican Cession, in 1848.
Why did many Northerners, such as Thoreau, oppose the Mexican-American War?
Critics feared new southwestern lands would become slave states.
Ready for more? Take the Unit 3 test.