Texas Independence & The Mexican-American War: Fifth Grade Social Studies
The turbulent annexation of the Republic of Texas and the subsequent Mexican-American War reshaped the borders of North America, adding over five hundred thousand square miles of western territory to the United States while reigniting the explosive national controversy over the expansion of slavery.
Mexican Texas and Anglo Settlement
In 1821, Mexico won its independence from Spain after an eleven-year war of liberation. Among Mexico's vast, sparsely populated northern territories was Tejas (Texas). To protect the region against hostile Comanche raids, stimulate economic growth, and establish border security, the Mexican government invited foreign settlers to move to Texas.
In 1822, Stephen F. Austin carried out his late father Moses Austin's dream by leading the "Old Three Hundred"—the first three hundred American families—into Texas. Austin operated as an empresario (a land agent granted large tracts of land by Mexico in exchange for recruiting settlers).
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| CONDITIONS FOR SETTLEMENT IN TEXAS |
| |
| MEXICO'S REQUIREMENTS: ANGLO SETTLERS' ACTIONS: |
| 1. Convert to Roman Catholicism - Most remained Protestants |
| 2. Become loyal Mexican citizens- Maintained American identity|
| 3. Obey all Mexican laws - Spoke English, kept U.S. ties|
| 4. ABOLISH SLAVERY (1829) - Brought enslaved African |
| Americans; disguised them as|
| "indentured servants for life|
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By 1830, the policy had succeeded all too well. More than twenty thousand Anglo-Americans flooded into Texas, outnumbering Mexican residents (Tejanos) by four to one. Settlers made little effort to assimilate into Mexican culture: they spoke English, established their own schools, remained Protestant, and ignored Mexican trade regulations. Most critically, when Mexico officially abolished slavery in 1829, Anglo settlers defiantly refused to free their enslaved laborers, signing them to fraudulent ninety-nine-year labor contracts.
Alarmed by the growing American influence, the Mexican government enacted the Law of April 6, 1830. This law banned further American immigration into Texas, placed heavy import tariffs on American manufactured goods, and established Mexican military garrisons across the province. Tensions escalated dramatically in 1834 when General Antonio López de Santa Anna seized power in Mexico City, dissolved the Mexican constitution of 1824, dismissed state legislatures, and established a centralized military dictatorship.
The Texas Revolution (1835-1836)
Texans, joined by many Tejanos who opposed Santa Anna's tyrannical central government, decided to fight for their rights. The first shots of the Texas Revolution were fired on October 2, 1835, in the town of Gonzales. When Mexican soldiers attempted to reclaim a brass cannon loaned to the town for defense against Native attacks, local Texans raised a homemade white flag emblazoned with a painted cannon and the defiant challenge: "Come and Take It!" The Texans drove off the Mexican soldiers, sparking armed revolution.
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| KEY MILESTONES OF THE TEXAS REVOLUTION |
| |
| 1. BATTLE OF GONZALES (October 1835) |
| - "Come and Take It!"; opening battle of the revolution |
| |
| 2. BATTLE OF THE ALAMO (Feb 23 - March 6, 1836) |
| - 187 defenders hold off 3,000 Mexican troops for 13 days |
| - All defenders killed (Travis, Bowie, Crockett) |
| |
| 3. TEXAS DECLARATION OF INDEPENDENCE (March 2, 1836) |
| - Republic of Texas born; Sam Houston named commander |
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| 4. GOLIAD MASSACRE (March 27, 1836) |
| - Over 300 surrendered Texan prisoners executed by order |
| of Santa Anna; fuels outrage |
| |
| 5. BATTLE OF SAN JACINTO (April 21, 1836) |
| - Houston surprises Santa Anna; battle won in 18 minutes! |
| - Santa Anna captured; signs treaties granting independence|
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The Battle of the Alamo
In February 1836, General Santa Anna marched an army of thousands of soldiers north into San Antonio to crush the rebellion. Approximately 187 Texan and Tejano volunteers retreated into the Alamo, a crumbling, walled Spanish mission. The garrison was co-commanded by twenty-six-year-old Lieutenant Colonel William B. Travis and legendary frontier knifefighter Jim Bowie, and included famous former Tennessee congressman Davy Crockett.
Santa Anna surrounded the Alamo and raised a blood-red flag from the San Fernando Cathedral, signaling "no quarter"—meaning no prisoners would be spared. In response, Travis fired a single cannon blast and penned an immortal letter addressed "To the People of Texas & All Americans in the World," declaring: "I shall never surrender or retreat... I call on you in the name of Liberty, of patriotism & everything dear to the American character, to come to our aid... VICTORY OR DEATH."
For thirteen days, the small band of defenders held off repeated assaults. Finally, before dawn on March 6, 1836, Santa Anna unleashed a massive, four-column infantry attack. Mexican buglers sounded the chilling notes of El Degüello, an ancient tune indicating that all defenders would be put to the sword. Mexican soldiers scaled the walls, breached the courtyard, and engaged in savage hand-to-hand combat. Every single Alamo defender was killed.
While the Battle of the Alamo was a tactical defeat, it bought invaluable time for Texas leaders meeting at Washington-on-the-Brazos to officially declare independence on March 2, 1836, draft a constitution for the Republic of Texas, and appoint General Sam Houston as commander in chief.
"Remember the Alamo!": The Battle of San Jacinto
Three weeks after the Alamo, Mexican forces captured and executed over three hundred Texan prisoners of war at Goliad. The twin massacres at the Alamo and Goliad inflamed Texan fury and united the rebellion.
General Sam Houston conducted a brilliant strategic retreat eastward, drawing Santa Anna's overextended army far from its supply lines. On the afternoon of April 21, 1836, Houston discovered Santa Anna's camp resting near the San Jacinto River. While Mexican troops were taking an afternoon siesta, Houston launched a surprise assault. Charging across the tall grass with fixed bayonets, the Texans shouted their vengeful battle cries: "Remember the Alamo! Remember Goliad!"
The Battle of San Jacinto was over in just eighteen minutes. The Texan army routed the Mexican forces, killing over six hundred Mexican soldiers and capturing Santa Anna the following day disguised as a common private. To save his life, Santa Anna signed the Treaties of Velasco, ordering all Mexican troops to withdraw south of the Rio Grande and recognizing Texas independence.
The Lone Star Republic and the Annexation Crisis
For nine years (1836-1845), Texas existed as an independent nation known as the Republic of Texas (often called the "Lone Star Republic"), with Sam Houston serving as its first president. Texans overwhelmingly favored annexation—joining the United States.
However, the United States hesitated. Adding Texas to the Union was fraught with political peril:
- The Slavery Controversy: Texas entered the world as a slaveholding republic. Northern abolitionists and lawmakers vehemently opposed admitting Texas, fearing it would upset the delicate balance between free states and slave states in the Senate and expand slavery's political power.
- Threat of War with Mexico: Mexico never recognized the Treaties of Velasco, maintaining that Santa Anna had signed them under duress as a prisoner of war. Mexico warned that American annexation of Texas would be treated as an act of war.
The stalemate was broken by the presidential election of 1844. Democratic candidate James K. Polk ran on an aggressive, expansionist platform embracing Manifest Destiny, promising to annex Texas and acquire all of Oregon. Following Polk's victory, outgoing President John Tyler pushed through a joint congressional resolution, and Texas was officially admitted as the twenty-eighth state in December 1845.
The Mexican-American War (1846-1848)
Immediately following annexation, the United States and Mexico clashed over a disputed border. The United States claimed that the southern border of Texas was the Rio Grande, based on the Treaties of Velasco. Mexico insisted that the historic border of Texas had always been the Nueces River, roughly one hundred and fifty miles farther north. The territory between the two rivers became a dangerous, contested no-man's-land.
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| THE BORDER DISPUTE & OUTBREAK OF WAR |
| |
| U.S. CLAIM: Rio Grande is the border |
| MEXICAN CLAIM: Nueces River is the border |
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| JANUARY 1846: |
| - President Polk orders General Zachary Taylor to march |
| 4,000 U.S. troops into the disputed territory on Rio Grande|
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| APRIL 1846: |
| - Mexican cavalry crosses the Rio Grande, attacks Taylor's |
| patrol, killing 11 American soldiers |
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| POLK'S WAR MESSAGE: |
| - "Mexico has passed the boundary of the United States, has |
| invaded our territory, and shed American blood upon |
| the American soil!" |
| - Congress declares war on May 13, 1846 |
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President Polk dispatched John Slidell to Mexico City with an offer to pay $30 million for California and New Mexico and forgive Mexican debts in exchange for recognizing the Rio Grande border. When Mexican leaders refused to receive Slidell, Polk ordered General Zachary Taylor to march four thousand soldiers into the disputed strip across from Matamoros on the Rio Grande.
On April 25, 1846, Mexican forces crossed the Rio Grande and engaged Taylor's cavalry patrol, killing eleven American soldiers. Polk seized upon the clash, sending an impassioned war message to Congress: "Mexico has passed the boundary of the United States, has invaded our territory, and shed American blood upon the American soil!" On May 13, 1846, Congress declared war.
A Three-Pronged Military Campaign
The Mexican-American War was fought across three major theaters:
1. Northern Mexico: General Zachary Taylor (nicknamed "Old Rough and Ready") crossed the Rio Grande, won dramatic victories at Palo Alto and Monterrey, and crushed a massive counterattack by Santa Anna at the Battle of Buena Vista in February 1847.
2. The West and California: General Stephen Kearny marched the "Army of the West" from Fort Leavenworth, Kansas, capturing Santa Fe, New Mexico, without firing a shot. In California, American settlers led by explorer John C. Frémont launched the Bear Flag Revolt in June 1846, declaring California an independent republic before joining forces with U.S. Navy Commodore John D. Sloat to secure the region.
3. The Invasion of Central Mexico: Recognizing that northern victories would not force Mexico to surrender, Polk ordered General Winfield Scott ("Old Fuss and Feathers") to execute an ambitious amphibious landing at Veracruz. In March 1847, Scott completed the first major amphibious landing in U.S. military history, followed the historic invasion route of Hernán Cortés across the mountains, and stormed Chapultepec Castle to capture Mexico City in September 1847.
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| THE TREATY OF GUADALUPE HIDALGO (1848) |
| |
| 1. BORDER RECOGNIZED: Rio Grande officially confirmed as the |
| southern border of Texas. |
| |
| 2. THE MEXICAN CESSION: Mexico cedes 525,000 square miles of |
| territory (55% of its pre-war land area!) to the U.S. |
| - Modern states: California, Nevada, Utah, Arizona, and |
| parts of New Mexico, Colorado, and Wyoming |
| |
| 3. U.S. COMPENSATION: United States pays Mexico $15 million |
| and assumes $3.25 million in American claims against Mexico|
| |
| 4. RIGHTS OF MEXICAN CITIZENS: Guaranteed property rights, |
| religious freedom, and right to become U.S. citizens |
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The Treaty of Guadalupe Hidalgo and Its Aftermath
On February 2, 1848, American diplomat Nicholas Trist and Mexican representatives signed the Treaty of Guadalupe Hidalgo, formally ending the war. Under the treaty, Mexico ceded more than five hundred and twenty-five thousand square miles—over fifty-five percent of its national territory—known as the Mexican Cession. In return, the United States paid Mexico $15 million and assumed over $3 million in American citizens' claims against the Mexican government. In 1853, the United States purchased an additional strip of southern Arizona and New Mexico from Mexico for $10 million in the Gadsden Purchase to build a southern transcontinental railroad.
The victory fulfilled the continental vision of Manifest Destiny, extending the United States from "sea to shining sea." However, it came at an immense moral and political cost:
- Dispossession of Mexican Americans: While the treaty guaranteed the property rights of the seventy-five thousand Mexican citizens living in the ceded lands, American legal courts, land squatters, and discriminatory taxes systematically stripped generations of Mexican Americans of their ancestral ranchos and civil standing.
- The Catastrophic Slavery Dilemma: The acquisition of this vast western empire reopened the explosive question of slavery with uncontrollable fury. Should slavery be permitted in the territories carved from the Mexican Cession? In 1846, Pennsylvania Representative David Wilmot proposed the Wilmot Proviso, demanding that slavery be banned in all territory acquired from Mexico. Although the proviso failed to pass the Senate, it sparked bitter sectional hatred between North and South that set the United States on an inescapable path toward the Civil War.
Chapter Review and Exercises
Summary Review Exercises
Exercise One asks students to explain why Mexico initially encouraged American settlement in Texas in the 1820s, and analyze the cultural and political factors that led to the Texas Revolution in 1835. The response should explain that Mexico sought settlers to develop the economy and provide defense against Comanche raids, detailing how Anglo settlers' refusal to assimilate, retain Roman Catholicism, speak Spanish, and obey Mexican laws banning slavery sparked severe political clashes when Santa Anna instituted a military dictatorship.
Exercise Two asks students to recount the significance of the Battle of the Alamo and the Battle of San Jacinto in the Texas Revolution. The response should describe how the thirteen-day siege of the Alamo and the martyrdom of Travis, Bowie, and Crockett bought crucial time for Texas leaders to declare independence, and explain how Sam Houston's surprise victory at San Jacinto routed Santa Anna's army in eighteen minutes, securing Texas independence.
Exercise Three requires students to analyze the border dispute that ignited the Mexican-American War in 1846 and outline the terms of the Treaty of Guadalupe Hidalgo of 1848. The response should explain the conflicting claims between the Rio Grande and the Nueces River, President Polk's deployment of troops into the disputed zone, and detail the treaty terms where Mexico ceded the Mexican Cession (over 525,000 square miles) for $15 million, highlighting how the new territory re-ignited the national debate over slavery.
Detailed Solutions
Solution to Exercise One clarifies that Mexican immigration policies created unintended demographic consequences. Within a decade, Anglo-Americans vastly outnumbered native Tejanos, importing American cultural norms and the institution of human enslavement, creating an ideological conflict that ignited when Mexico attempted to reassert national authority.
Solution to Exercise Two reveals that the Alamo served as a powerful emotional and military catalyst. The sacrifice of its defenders inspired the vengeful rallying cry "Remember the Alamo!" that propelled Sam Houston's troops to victory at San Jacinto, transforming a desperate retreat into the birth of an independent republic.
Solution to Exercise Three details that the Mexican-American War was an intentional manifestation of Polk's expansionist policies. By leveraging the disputed Texas borderlands, the United States acquired a vast continental domain, fulfilling the dream of Manifest Destiny while unleashing the toxic sectional debate over slavery that led directly to the American Civil War.