Explain the effects of the Mexican–American War on the United States.

1. Objectives • Explain the effects of the Mexican–American War on the United States. • Trace the causes and effects of the California Gold Rush. • Describe the political impact of California’s application for statehood.

2. Terms and People • Treaty of Guadalupe Hidalgo – 1848 agreement formally ending the Mexican–American War, included the sale of Mexican territory to the U.S. • Gadsden Purchase– 1853 sale of Mexican territory in Arizona and New Mexico to the U.S. • Wilmot Proviso– proposed law that would have banned slavery in territory obtained from Mexico • California Gold Rush – mass migration of gold seekers into California in 1848 and 1849

3. Terms and People(continued) • forty-niners – those attracted to California by the Gold Rush in 1849 • placer mining– use of metal pans, picks, and shovels to look for gold along streams and rivers • hydraulic mining– use of jets of water that erode hillsides into long sluiceways to catch gold

4. What were the effects of the Mexican–American War and the California Gold Rush? The quick victory in the Mexican–American War and gold in California fed into the expansionists goals of Manifest Destiny. The war also highlighted growing differences between the North and South and set the stage for future conflict.

5. Mexico had to sell a third of its territory to the United States (1.2 million square miles). • For $15 million, the U.S. obtained California and New Mexico. The Texas border was set at the Rio Grande River. • Mexico was humiliated and remained bitter toward the United States for decades. As a resultof the loss, Mexico was forced to sign the Treaty of Guadalupe Hidalgo.

6. Territory in southern Arizona and New Mexico was purchased from Mexico as a potential route for a transcontinental railroad. • The lands obtained from Mexico increased the area of the United States by a third. • The land formed New Mexico, California, Nevada, Utah, Arizona, and half of Colorado. In 1853, the United States made the Gadsden Purchase.

8. Purchase of the Mexican Cession caused a debate over the expansion of slavery. • In 1846, the Wilmot Proviso suggested a ban on slavery in the territories obtained from Mexico. • The Proviso passed in the House, but failed in the Senate. Both Whigs and Democrats voted along sectional lines. • The Proviso brought the issue of slavery before Congress, which for decades tried avoid the topic.

9. In 1848, gold was foundat Sutter’s Mill on the American River near Sacramento, California. The resulting California Gold Rush brought a mass-migration of 80,000 fortune hunters west. They were called forty-niners. Half traveled overland; the rest either sailed around South America or to Panama, where they crossed the isthmus and caught ships up the coast.

10. The Gold Rush attracted miners from South America and China. California’s population grew from 14,000 in 1847 to 225,000 in 1852. • The first miners used metal pans, shovels and picks to find gold along river banks. Few became wealthy using this method, called placer mining. • Merchants and traders made more money selling goods to the miners than the miners earned themselves.

11. Life in the mining camps was crude and rough. Many died of disease, especially cholera and dysentery. Fights and violence were common. Only a few of the miners were women.

12. Mining soon mechanized to make it more efficient. One method was to divert a river or stream to expose the river bed. • Hydraulic mining employed jets of water to erode gravel hills into long lines of sluiceswhich caught the gold. Hydraulic mining left heavy sediments in the river and caused a great deal of environmental damage.

13. Some tried “hard rock” mining, where men searched for gold in deep tunnels supported by wooden posts and beams. Gold mining soon became too expensive for individual miners. The “democratic” era in the gold fields did not last long. Individual prospectors were soon replaced by wealthy investors paying wages.

14. White miners quickly asserted control in California. Minorities faced violence in the gold fields and discrimination in the courts. Native Americans were killed or lost their land. Others found work on farms and ranches. Old Mexican land titles were generally ignored. Most of the original Californians were dispossessed. The Chinese were targeted by a foreign miner’s tax and mob violence. Mexicans also had to pay a foreign miner’s tax.

15. San Francisco became the gateway to the California gold fields. After 1848, the city grew rapidly from a tiny Spanish settlement into the major west coast American city. Source: CIA World Factbook Online

16. Most Californians opposed slavery so California’s admission as a free state would tip the 15 slave and 15 free statebalance in the U.S. Senate. Debate over the spread of slavery into the territories obtained from Mexico became a leading cause of the Civil War. By October 1849, California prepared toseekadmission into the Union.

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