France invaded Mexico to install a puppet monarchy and recover debt

France, Spain, and Britain formed a joint military alliance to force Mexico to repay its debts

In October 1861, the three powers signed the Convention of London and landed troops at Veracruz that December. Britain and Spain reached settlements with Mexico and withdrew. France refused and aimed to change the regime in power in Mexico.

Some historians claim that Mexico's victory at Puebla may have prevented France from arming the Confederacy

According to some experts, Napoleon III planned to ship weapons from Mexico to Confederate forces to break the Union naval blockade. The delay caused by the Battle of Puebla meant French resources didn't reach the Texas border until after the Union Army's decisive victory at Vicksburg.

Mexico’s political chaos weakened its defense against US invasion

Mexico’s post-independence instability—marked by coups, power struggles, and weak central control—left its northern frontier vulnerable. That political fragmentation shaped Mexico’s unpreparedness during the Mexican-American War and helped enable US conquest.

Mexico admired Lincoln for opposing the war and supporting Mexican sovereignty

As a congressman, Abraham Lincoln condemned the Mexican-American War as unjust. Years later, as president, he backed Mexico’s fight against French occupation. His principled stance earned enduring respect and monuments across Mexico.

Cinco de Mayo celebrates the Mexican victory at the Battle of Puebla

On May 5, 1862, Mexican forces under General Ignacio Zaragoza repelled a larger, more well-equipped French army at Puebla. The French endured roughly 500 deaths before retreating. Though the French ultimately captured Puebla a year later, the improbable one-day victory became a symbol of national pride.

Manifest destiny fueled US aggression against Mexico

The belief that the United States had a divine right to expand westward—known as manifest destiny—justified President Polk’s push for territorial conquest. It shaped public support for the Mexican-American War and framed the invasion as national destiny.

President Polk deliberately provoked war with Mexico

After Mexico refused to sell California and New Mexico, President James K. Polk ordered US troops into disputed territory between the Nueces River and the Rio Grande—knowing it would likely spark a conflict. When fighting broke out, he used it to justify declaring war.

The US won every major battle of the Mexican-American War

Despite being outnumbered in key engagements, US forces defeated Mexican armies across every major front. Superior training, leadership, and logistics allowed the US to win decisively—capturing Mexico City without losing a single major battle.

The Aztec Empire ruled over 80,000 square miles of central Mexico for nearly a century—until a small band of Spanish conquistadors brought it down in 1521.

How the US took half of Mexico

In just two years, the United States redrew the map of North America. Sparked by border disputes in Texas and fueled by President James Polk’s drive for expansion, the Mexican–American War (1846–1848) reshaped both nations.

The Treaty of Guadalupe Hidalgo forced Mexico to surrender over half its territory

Signed in 1848, the Treaty of Guadalupe Hidalgo ended the war but came at a steep cost for Mexico—ceding 55% of its territory, including California and the Southwest, in exchange for $15 million and vague promises to protect Mexican residents.

Learn how Mexico’s anti-slavery stance shaped the US–Texas conflict

Historian Alice Baumgartner explores how Mexico’s abolition of slavery clashed with Anglo settlers' ambitions in Texas. The episode reveals how enslaved people fled south to freedom, reshaping the politics that led to Texas independence and the Mexican-American War.

See the path Spanish conquistadors took to conquer the Aztecs

Spanish expeditions reached central Mexico as the Aztec Empire was expanding its influence. After securing bases in the Caribbean, they advanced west into Aztec territory, triggering a cascading conflict depicted in this interactive map and timeline.

Hear about why Europe obeyed the Monroe Doctrine, despite American military weakness

This podcast explores the European background of the Monroe Doctrine, highlighting France's efforts to install aristocratic Bourbon monarchs in the newly independent Latin American republics—and how US opposition, British threats, and Spanish resistance ultimately disrupted those plans.

US troops committed widespread atrocities during the Mexican-American War

American volunteer regiments frequently looted towns, raped civilians, and executed prisoners—especially in occupied northern Mexico. Historians have documented how racial hatred and impunity fueled war crimes that were rarely punished by military leadership.

The Aztec capital of Tenochtitlan fell after a brutal 75-day siege.

American annexation of Texas eventually sparked war with Mexico

After Texas won independence from Mexico in 1836, the US annexed it in 1845—despite Mexico’s refusal to recognize Texas as separate. That annexation, combined with a heated border dispute, triggered the Mexican-American War the following year.

The Aztec Empire began as a three-city military alliance

The Aztec Empire emerged in 1428 when Tenochtitlan, Texcoco, and Tlacopan formed the Triple Alliance, combining military power and tribute networks. This pact transformed the three city-states into a dominant regional empire that rapidly expanded across central Mexico.

Zachary Taylor became a national hero during the Mexican-American War

General Zachary Taylor led US forces to key victories in northern Mexico, earning widespread fame for his leadership. His popularity from the war propelled him to the presidency in 1848.

New research challenges the myth that Montezuma peacefully surrendered to Spain

For centuries, historians claimed Montezuma II willingly ceded control to the conquistadors, and that later Aztec resistance was a rogue uprising. Evidence now shows no peaceful handover occurred, revealing a far more turbulent and contested encounter between the two warring empires.

The Monroe Doctrine helped lead to the American occupation of territory abroad

This podcast explores how the policy motivated a century of US military intervention throughout Latin America, the Caribbean, and the Pacific—covering the annexation of Hawaii, the Spanish-American War, and occupations of Cuba, Haiti, and Panama.

The Compromise of 1850 tried to settle disputes over land gained from Mexico

Territory acquired in the Mexican-American War reignited fierce debates over slavery’s expansion. The Compromise of 1850 aimed to ease tensions by admitting California as a free state and letting other territories decide the issue—but the compromise ultimately failed and helped pave the way to the Civil War.

A wave of Latin American independence movements most likely prompted the Monroe Doctrine

Between 1810 and 1822, many Latin American colonies separated from Spanish rule, 10 in the last two years. Concerns that Spain and its European allies might try to regain these republics were a main reason behind Monroe's declaration.

Support for slavery helped drive Texas to revolt against Mexico

Mexico abolished slavery in 1829, but many Anglo-American settlers in Texas brought enslaved people and refused to comply. Their desire to preserve slavery was a major factor in Texas’s 1836 rebellion and independence from Mexico.

The British Royal Navy—not the US military—enforced the Monroe Doctrine for most of the 19th century

In the early to mid-1800s, the US lacked the ships and military power to prevent European nations from colonizing the Americas. Britain enforced this to protect its commercial interests by keeping rival European powers out of Latin America.

Mexican Independence Day is celebrated on September 16

Cinco de Mayo is widely mistaken for Mexican Independence Day. September 16 is the actual date, commemorating the 1810 Grito de Dolores, Father Miguel Hidalgo's call to revolution that launched Mexico's war against Spanish colonial rule.

FDR's Good Neighbor policy reversed the interventionism that had grown from the Monroe Doctrine

Franklin Roosevelt pledged in his 1933 inaugural address to be a "good neighbor" to Latin America and to oppose armed intervention by American forces. His administration withdrew troops from previous occupations and signed a multilateral agreement stating that no state has the right to interfere in another's affairs.

The Continental Army invaded Canada in an attempt to seize Montreal and Quebec City in 1775.

Irish immigrants deserted the US Army to fight for Mexico

During the Mexican-American War, hundreds of Irish Catholic immigrants—facing discrimination in the US Army—defected to Mexico and formed the Saint Patrick’s Battalion. Though many were captured and executed, they remain honored as heroes in Mexico.

Jefferson feared European control in the West of North America

Jefferson pushed for the Louisiana Purchase to prevent France or Spain from dominating the western frontier, securing control of the Mississippi River and vast lands that he felt were essential to America’s strategic and economic future.

The diplomat who implemented Monroe's policy introduced the poinsettia to the United States

Joel Roberts Poinsett, appointed as the first US minister to Mexico in 1825 following the doctrine's announcement, took cuttings of a vibrant Mexican plant called the cuetlaxochitl during his time there. Americans loved the foliage and named it after him.

John Marshall gained national prominence during the XYZ Affair

In 1797, President John Adams sent Marshall to France amid seizures of American ships. French intermediaries demanded loans and bribes before talks, and Marshall refused. Publication of the dispatches fueled the Quasi-War and elevated his reputation in the United States.

The Roosevelt Corollary transformed the Monroe Doctrine from a defensive warning into a rationale for US military intervention

In 1904, President Theodore Roosevelt declared that the US had the right to exercise international police power in Latin America. Over the following two decades, the US intervened militarily in the region about a dozen times—often enough that Marines became known locally as "State Department troops."

Future President Abraham Lincoln challenged Polk’s justification for war with Mexico

As a freshman congressman, Abraham Lincoln introduced the “Spot Resolutions,” demanding President Polk prove that Mexico had attacked on US soil. This constituted Lincoln’s first major political stand and highlighted growing dissent over the war.

Puebla holds an annual battle reenactment on Cinco de Mayo

Each May 5, the city of Puebla marks the anniversary with festivals and a full military reenactment of the 1862 battle. While Cinco de Mayo is barely observed elsewhere in Mexico, it remains a ceremonial source of local pride in the state where the battle was actually fought.

Foreign policy and war defined Madison's presidency

During James Madison's presidency, disputes with Britain and France over trade, maritime rights, and impressment dominated foreign policy, culminating in the War of 1812 and shaping how the United States engaged with major European powers.

The US Army inherited the Apache Wars after the Mexican-American War

The resolution of the Mexican-American War inserted the US Army into an ongoing conflict between Apache groups and outside powers—transforming local resistance into a decades-long struggle against American expansion known as the Apache Wars.

The US intervened in Latin America to block communist influence during the Cold War

Fearing Soviet expansion, the US intervened across Latin America by backing coups, funding right-wing regimes, and supporting anti-communist militias—most notably in Cuba, Chile, Nicaragua and Guatemala.

The Monroe Doctrine was designed to keep Europe out of the Americas

First articulated in 1823 by President James Monroe, the doctrine declared the Western Hemisphere off limits to European colonization. It has since been invoked to justify US military interventions in Latin America, from Teddy Roosevelt's takeover of Venezuela to George H.W. Bush's arrest of Panama's leader Manuel Noriega.

The Mexican-American War led to the birth of the Associated Press

To cover the distant war efficiently, rival New York newspapers pooled resources to share reports from the front—forming what became the Associated Press. The war marked a turning point in how Americans received real-time news about foreign conflicts.

How the US entered WWI in 1917

Originally taking a position of neutrality during the course of World War I, the United States of America eventually relented. Entering the war in 1917, support for the British and French had risen and Americans were incensed by Germany's overtures to Mexico and U-boat attacks that sank ships and ended American lives. See how and why the US entered WWI in this article.

The Mexican-American War trained future Civil War generals

Many key military leaders of the Civil War—including Ulysses S. Grant, Robert E. Lee, and Thomas “Stonewall” Jackson—first saw combat in the Mexican-American War, gaining battlefield experience that shaped their later commands.

Cinco de Mayo holiday celebrations originated with California's Mexican Americans during the Civil War

California Latinos first celebrated Cinco de Mayo in 1862 through patriotic assemblies called Juntas Patrióticas. Ardent Union supporters, these individuals saw the Puebla victory as a win for democracy against both French imperialism and the Confederate cause.

Madison urged Jefferson to accept the Louisiana Purchase despite constitutional concerns

As secretary of state, James Madison helped negotiate the 1803 Louisiana Purchase and persuaded Thomas Jefferson to proceed, arguing that the strategic and economic stakes outweighed the unresolved constitutional questions.

What was the French Revolution?

This 12-minute video provides an overview of the French Revolution of 1789, a conflict brewed from food shortages and economic hardships. On May 5, 1789, French King Louis XVI called a meeting of the three groups--known as estates--made up of...

Music of the French Revolution

Listen to the melodies of the French Revolution of 1789 in this resource by the Minneapolis Institute of Art. Reconstructed by three professionals, these 10 songs from France's revolutionary era offer a glimpse into the haunting realities of such change. The songs were recreated based on musical scores included in fashion magazines from the era. French and English lyrics are provided for each song.

As president, Thomas Jefferson expanded federal power despite opposing centralized authority

Although Jefferson argued for limited national power, his presidency expanded federal authority through actions such as the Louisiana Purchase, territorial governance, and federal enforcement—reflecting a pragmatic departure from his earlier strict interpretation of the Constitution.

European powers largely dismissed Monroe's declaration initially

The reaction in Europe ranged from quiet acceptance in Britain to outrage from Austria's Prince Metternich, who privately called it a "new act of revolt." At home, US newspapers reported a "warm and universal burst of applause," and Congress responded positively to the address.

Enslaved and in debt: the French roots of Haiti's struggles

This investigative infographic details how Haiti was forced to pay for its freedom twice: once in blood and once in cash. In August 1791, Haiti's enslaved population launched a revolt against French colonists, successfully establishing Haiti as a...

The Louisiana Purchase nearly doubled America’s size in 1803

Acquired from France for $15M, the Louisiana Purchase added 828,000 square miles to the United States—stretching from the Mississippi River to the Rockies. US ambassadors in France signed the papers to buy the tract from the embattled Napoleon Bonaparte for a mere $15M before Jefferson learned the terms, due to the advantageous nature of the deal.