The Mexican-American War

• “One of the most unjust wars ever waged.” –US Grant

• The war had been “unnecessarily and unconstitutionally” begun. – Abraham Lincoln

Background

• Manifest destiny plays a big part in the lead-up to the war

• The US government secretly (and sometimes not so secretly) attempts to acquire California & Texas in the 1830s and 1840s

• A. Jackson repeatedly tries to buy Texas from Mexico, but not successful. Sam Houston & Jackson are good friends. Coincidence?!?!?!

• Mexico is internally weak, and technically still at war with Texas until an armistice was signed in 1844

So where is the border?

• The Treat of Velasco signed in 1836 set the boundary between Mexico & Texas at the Rio Grande River

• The Mexican Congress declared this treaty invalid shortly after it was signed, and proclaimed that Texas was simply a rebellious province

• In 1844, an armistice is signed between Tex & Mex, but border issues remain

California, Fremont, & Slidell

• A federally commissioned expedition arrives in Cali in winter ‘45-’46, headed by John Fremont; Fremont claims he’s looking for a seaside house for his mother, Mex officials order him to leave

• President Polk sends John Slidell to Mexico City to negotiate the purchase of Texas & Cali in Nov ‘45, government refuses

• US officially annexes Texas on 12/29/45, all but assuring a conflict with Mexico

The Thornton Affair

• Polk sends US forces to the Nueces River in July ’45 to defend a possible invasion

• By late March ‘46, these same troops were on the border of the Rio Grande near modern-day Brownsville/Matamoros

• A US scouting party was attacked on April 25th by Mexican forces

• Polk cited this bloodshed on American soil as a clear, justified cause for war, which is declared on May 13th

Mass Communications

• In previous wars, couriers, mail, & word of mouth carried most news to the masses

• By the 1840s, newspapers created an extensive & expensive systems of steamships, railroads, pony express, & telegraphs to receive war news

• The “Penny Press” was very popular with Americans; cheap daily newspapers that kept up with latest war news

• Modern war correspondent appears

• Almost all US newspapers strongly supported the war, viewing it as positive and an inevitable part of manifest destiny

• War reporters tagged along and sometimes even fought with American armies, creating a soldier-reporter hybrid

• Thus, most reporting in the US was very biased, especially by today’s standards

• Mexican newspapers mirrored the instability of the nation

• In 1845, a very popular Mexican newspaper was “El Siglo XIX”

• El Siglo XIX initially opposed war and argued for peaceful negotiations, then switched its official position

• The Mexican press helped oust Herrera & Santa Anna from power

The Telegraph

• Invented by Samuel Morse in 1837, the telegraph plays a huge part in the M-A War

• The technology had been perfected by 1844• War news could be sent by mail to the coast, a

steamship would take it to New Orleans, & the telegraph office there would broadcast it to other cities

• War news could be dispersed in just a few days

Morse Code Activity!

• You are a lowly employee of the New Orleans Telegraph company and bored out of your mind! It is April 1846....

• You see a steamship pull into the harbor....• Suddenly a man bursts into your office and

delivers an urgent message!• You must telegraph this news throughout the

US! Quick, to the telegraph!

Opposition to the War

• Don’t be confused, the M-A War was NOT Vietnam on the US homefront!

• In 1846, 200,000 men answered the call for 50,000 volunteers in New York

• War enthusiasm was HIGH, and support for the war always remained strong

• Nevertheless, a vocal minority did oppose the conflict. WHO and WHY?

The Whigs

• The Whig Party existed from 1833-1860, & was the forerunner to the Republican Party

• The party formed in the 1830s to oppose Andrew Jackson & the Democratic party

• 3 presidents were Whigs: William Henry Harrison, Zachary Taylor, Milliard Fillmore

• Based on these facts, what do you think the Whigs believed in????

Famous Whigs

• Whigs strongly believed in public education, and preferred banking and industry over agriculture

• Think of the Whigs as city slickers and the Democrats as hicks

• Many Whigs were very religious, & over time many began to oppose slavery on moral grounds

• So why would some Whigs oppose the war??

• Lincoln made a controversial speech in 1847, criticizing the war and challenging president Polk to show Congress the spot where American blood had been shed on American soil; the Whigs would not nominate Lincoln for reelection

• Popular Whig Senator Henry Clay strongly condemned the war; he lost to Polk in 1844, arguing against annexation of Texas

Other Protests

• Abolitionists were extremely vocal about their opposition, believing the war was a giant land-grab designed to extend slavery

• William Lloyd Garrison, a famous abolitionist, openly rooted for Mexico to win in his newspaper The Liberator

• The most famous protest of the war was Henry David Thoreau’s refusal to pay a poll tax; he spent one night in jail, but wrote Civil Disobedience afterwards

Soldier Protests

• Desertion in the US army was around 8%, normal by 19th century standards

• Nevertheless, there were instances of dissatisfaction with the war among soldiers

• Harsh military life in the Mexican desert caused discontent among some units

• Cruel atrocities committed by some US soldiers shocked others, & some became disillusioned

• The main difference with other wars: soldiers had more of a voice through newspapers to get this info to the public

• A (in)famous instance of soldiers protesting was the Saint Patrick Battalion

• This battalion was made up of mostly Irish & German Catholics

• Many were soldiers in the US army in the 1840s, then defected to the Mexican army before the outbreak of war

• The Irish felt like second-class citizens in the US army, but felt more at home in Mexico

• The Mexican government constantly enticed US soldiers to desert, with promises of higher pay & land grants

• The San Patricio Battalion was initially an artillery unit, & used their knowledge of US tactics against their former employers

• Santa Anna ordered the San Patricios to become an infantry unit; they often fought hard, knowing they’d be killed for treason if caught

• After the war, many were caught and executed by hanging or firing squad

The Battles

Palo Alto & Resaca de la Palma

• Fought May 8-9, 1846 near Brownsville• Gen. Mariano Arista lays siege to Fort Texas

while Gen. Taylor & most of his troops are in Port Isabel

• Arista’s strategy is to get between Fort Texas & Port Isabel, dividing the American army

• This exact scenario occurs; look on googlemaps!

• The clash at Palo Alto was won by the Americans’ use of “flying artillery,” which was artillery that could be advanced rapidly

• Mexican artillery was old, heavy, & slow• US artillery causes Mexicans to withdraw Palo Alto to a

dry stream called Resaca de la Palma• Mexican army had a better defensible position, but US

attacks & artillery are too much to overcome• Texas campaign is over, costing Mexico 335 killed &

335 wounded, US 60 killed 149 wounded

California Campaign

The Siege of Los Angeles

• The Bear Flag Revolt occurred in June 1846 in Sonoma; largely symbolic, having little actual effect

• In 1846, the city (or pueblo) of Los Angeles had around 1600 citizens, mostly Californios

• In August ‘46, 50 US Marines take LA easily; Mexican officials flee north, shocking the Californios in LA

• Jose Maria Flores, an officer who had remained, led a successful insurrection against the US forcing the Marines to withdraw by Sept 30

• Though ultimately unsuccessful, the Californios proved a worthy, fierce enemy to US forces

Californios!

Battle of San Pasqual

• Gen Stephen Kearney marched 200 US forces from Santa Fe to San Diego to assist in the conquest of California

• 160 Californio lancers block his advance at San Pasqual Valley

• On Dec 6, 1846 US forces charged the Californios; the charge was unorganized & strung out, & the musket powder had been rained on

• The mules pulling the US cannons bolted; Californios used their superior horsemanship to ride down, rope, & stab US soldiers with their lances, killing 19 & wounding 15

• Despite victory, Californios retreated & US arrived in San Diego

Battle of Buena Vista

• February 1847, showdown between Taylor & Santa Anna, US nearly loses, bloodiest battle of the war

• Many of Taylor’s forces had been recalled, & his was disobeying orders to stay in Monterrey

• News from Mexico City warns Santa Anna that there is chaos in the capitol; he is forced to retreat back to Mexico City

Scott’s Mexico City Campaign

• Instead of reinforcing Taylor, Polk orders Winfield Scott to conduct a separate campaign

• Seizes the Port of Veracruz on March 29, 1847• Fights a series of engagements, and pushes

Santa Anna back to Mexico City• Between Sept 8-15, US forces lay siege to

Mexico City; main assault on the city is the storming of Chapultepec Castle on Sept 12

• Chapultepec was a fort built in 1785, and sat atop a hill overlooking the city

• Scott ordered a shelling of the fort, followed by an infantry assault the following day

• Despite a strong defense by the Mexicans, and the strong position of the castle, US forces climb the cliffs and storm the castle

• Once Chapultepec is taken, the Mexican defense collapses, & Santa Anna abandons the city

• US forces occupy Mexico until the Treat of Guadalupe Hidalgo ends the war in Feb 1848

Los Ninos Heroes

• “The Boy Heroes” of the Battle of Chapultepec

• Young boy soldiers ranging in age from 13-19 who refused to surrender Chapultepec; all died in battle

• Celebrated as national heroes in Mexico

Parting Thoughts...

• Why did the Mexican-American War occur?• Was this war a “just” war?• Why/how was the United States victorious?• Who are the heroes of the war?• What does the war mean today? Does it have

any modern meaning?