MEXICAN-AMERICAN WAR

1846-1848

Manifest Destiny The belief that we had a God-

given duty to expand the nation from coast to coast

President James K. Polk was a big believer in Manifest Destiny

Border ControversyControversy arose over the southern border of Texas

Mexico claimed the border was a the Nueces River

U.S. claimed it was at the Rio Grande

Creating a War An American force, led by Gen.

Zachary Taylor, entices a patrol of Mexican troop to fire on American soldiers killing one

President Polk claiming that Mexico had invaded the U. S., asks for a declaration of war and receives it

May 1846 – Palo Alto, Mexico Zachary Taylor leads 1,700 U. S.

soldiers against an estimated 7,500 Mexican soldiers and defeats them in front of several Whig newspapermen

Taylor is made an immediate national hero

Meanwhile ... June 1846 – U. S. and Great

Britain negotiate a treaty making the current boundary between the United States and Canada at the 49th parallel

The land of the Oregon Territory below this border now belongs exclusively to the United States

And now, back to the war

June 1846 – settlers of California, with the help of Gen. John C. Fremont and Commodore John Sloat claim California is independent of Mexico and two months later it is annexed to the United States

August 1846 – U. S. army takes over Santa Fe without firing a shot and announces the annexation of New Mexico

January 1847 – Gen. Winfield Scott lands 9,000 troops at Vera Cruz – he plans to follow the same route that Cortez took to Mexico City

February 1847 – U. S. forces numbering about 5,000 men, under Gen. Taylor capture Buena Vista, Mexico

This ends the war in the northern region of Mexico

By, defeating 15,000 Mexican “troops”, Taylor is again marked by a hero by Whig newspapermen

The defeated “troops” consist mostly of peasants

September 1847 – Troops under Gen. Scott capture Mexico City

March 1848 – U. S. and Mexican governments sign the Treaty of Guadalupe Hidalgo

Treaty of Guadalupe Hidalgo

The U. S. –Mexico border set at the Rio Grande

U. S. receives more than 500,000 square miles of land from Mexico (this area eventually becomes the states of CA, NV, and UT, and parts of NM, AZ, CO, and WY) for $15 million

Mexico pays $3.25 million for “costs of war”

Legacy of War

U. S. achieves Manifest Destiny Mexico loses 2/5’s of its territory Generals Scott and Taylor become

national heroes Officers get valuable military training

in wartime – this experience would be used years later in the Civil War

Land acquired in the treaty of Guadalupe Hildalgo becomes the cornerstone of the slavery issues that led directly to the Civil War

Gadsden Purchase

United States purchases about 30,000 square miles for $10 million

The area becomes the southern part of NM and AZ