US-MEXICAN WAR1846-1848“Mr. Polk’s Little War”

Causes of the War• Mexico is upset with the annexation of Texas in 1845.

• James K. Polk is elected President on a pro-expansion platform.

• The continued border dispute between

Nueces River (Mexico’s claim)

and Rio Grande River (US claim).

“Purposeful Polk” and John Slidell’s mission• In November 1845, President Polk sent John Slidell to

Mexico to negotiate a settlement.

• Slidell was authorized to:- accept the Rio Grande River as the southern border of US.- Offer $5 million dollars for the purchase of New Mexico territory.- Offer $25 million dollars for the purchase of California.

• Mexico had expected to:- discuss the return of (or at least compensation for) Texas.

• Mexican President Herrera refused to see Slidell and threatened to have him arrested.

Polk

Herrera

Slidell

“Purposeful Polk” andZachary Taylor • Jan. 1846, Polk orders General Zachary Taylor, “Old Rough

and Ready,” and US forces to Texas to prepare to defend the border and a US naval force is sent into the Caribbean Sea.

• March 1846, Taylor crosses the Nueces River in an effort to establish fortifications along the Rio Grande River.

• April 1846, Mexican forces cross Rio Grande and fights with US scouting party. 11 Americans die

• May 1846, Polk presents war message to Congress and war is declared two days later.

Polk

Taylor

California joins the fight• In June 1846, Californians led by John C. Fremont

captured the town of Sonoma from Mexican officials. They use Polk’s offer to buy California and pledges of military support to explain actions.

• These Americans declare independence from Mexico and call themselves the Bear Flag Republic.

• By Dec. 1846, Col. Stephen Kearney arrives in California and supports the Bear Flag rebels.

Opposition to War• Although Polk won the election of 1844 based on his pro-

expansion plans, some Americans did oppose going to war with Mexico.

1) Abolitionists feared that any territory gained from the war would become slavery states.

2) Illinois Congressman Abraham Lincoln sponsored the “Spot Resolutions” which questioned Polk’s reasons for the war.

3) Pennsylvania Congressman David Wilmot added “provisos” to laws paying for the war that would deny slavery in all lands gained from Mexico.

4) Massachusetts author Henry David Thoreau went to jail for refusing to pay taxes that supported the war. Wrote these ideas down in an essay called “Civil Disobedience.”

Lincoln Thoreau

Wilmot

Fighting and Winning the War: 1847-1848

• The Mexican Army suffered from a lack of supplies, modern weaponry and effective leadership.

• US able to divide the attention of the Mexico forces by fighting in the North (Gen. Taylor’s forces) and in Central Mexico (General Winfield Scott “Old Fuss and Feathers”).

• General Scott’s strategy involved an amphibious landing at Veracruz (March 1847) and a direct attack on the capital, Mexico City.

• Scott captured Mexico City on September 14, 1847.

Campaigns of the US-Mexican War

Polk

Trist

Scott

Ending the War: Feb. 2, 1848• Nicholas Trist, an American diplomat, was traveling with

General Scott with orders to attempt peace “if favorable.”

• After Mexico City falls and Santa Anna exiled (again), Trist begins negotiations with new Mexican government. Polk recalls Trist to Washington DC in order to stop peace talks.

• Trist ignores the orders and continues with the peace talks. Sends a 60-page letter of explanation to Polk.

Treaty of Guadalupe-Hidalgo• US gets:

• Rio Grande River is established as the border between the US and Mexico.

• LAND! The “Mexican Cession” includes 6 future states

(New Mexico, Arizona, Colorado, Utah, Nevada and California).

• Mexico gets:• $15 million dollars for the “Mexican Cession”• $3.5 million dollars for damage to Mexican property• Mexican citizens that remain on US territory will have rights.

Outcomes of the US-Mexican War

• Land exchange:

US increased by 1/3 and Mexico reduced by 1/2

• US military gained experience for Civil War:

Both Robert E. Lee and Ulysses S. Grant were with General Winfield Scott’s expedition to Mexico City.

• Gadsden Purchase and Mexican resentment:

In 1853, James Gadsden was sent to Mexico to purchase additional land for $10 million. Mexico agrees rather than go to war.

GrantLee