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

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.

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 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 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.

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.

Explore the social and cultural history of the Mexican-American War

Historian Peter Guardino joins host Don Wildman to explore how the war shaped ordinary lives on both sides of the border. Drawing from The Dead March, the episode reveals how culture, class, and ideology shaped the conflict and its consequences.

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.

Congress has formally declared war 11 times across five conflicts, the last in 1942

The five declared wars were the War of 1812, the Mexican-American War, the Spanish-American War, World War I, and World War II. Every major American military conflict since Korea, Vietnam, Iraq, and Afghanistan has been fought without a formal declaration.

The US Army massacred close to 300 Lakota men, women, and children at Wounded Knee in 1890

Fearing the Ghost Dance—a spiritual movement spreading across starving reservations—the Army surrounded a Lakota encampment at Wounded Knee Creek, South Dakota. When a shot was fired during an attempted disarmament, it sparked chaos, and soldiers killed nearly 300 people.

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.

US westward expansion—and the status of slavery in the new territories—was a major cause of the American Civil War

The addition of new western lands forced the nation to confront whether slavery would spread beyond the South. Each debate over the admission of a new state sharpened the divide between free and slaveholding regions.

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."

The Red Power movement pushed back against poverty and broken treaty rights in the 1960s and 1970s

Inspired by the Civil Rights Movement, Indigenous activists founded the American Indian Movement, a national advocacy organization, to protest excessive police violence and federal violations of treaty rights, drawing national attention to conditions on reservations.

American archaeology has a complicated legacy

Many national parks were discovered through American archaeological expeditions and, consequently, included the looting of Native American cultural sites and artifacts.

Before World War II, the US was a Pacific power

Decades before Pearl Harbor, the US held major Pacific territories—Hawaii, the Philippines, Guam, American Samoa, and numerous island bases—giving it strategic reach across the western Pacific. This presence increasingly overlapped with Japan’s imperial ambitions in the region, contributing to rising tensions.

King Philip’s War devastated Native resistance in colonial New England

Decades of rising tension over land and sovereignty erupted in 1675, when Wampanoag leader Metacom led a Native alliance against English colonies. The 14-month war ended in catastrophic defeat, killing thousands and shattering organized Native power in the Northeast.

The 2001 Authorization for Use of Military Force has been used by four administrations to justify military operations in 22 countries

Passed three days after the September 11 attacks to authorize the use of force against al-Qaeda and the Taliban, the 2001 AUMF has since been stretched far beyond its original scope and has been used by four consecutive administrations to justify military operations.

Explaining the final battle of World War I

The Meuse-Argonne Offensive was the last battle of the First World War. Beginning in September and ending November 11, 1918, the battle was a tumultuous event and the first time the American Army fought on the world's stage. America simultaneously achieved victory and discovered new methods to fight a war. This Apple History podcast provides the details.

What happened after the Civil War?

After the massive devastation and scorched earth wartime methods of the Civil War, the US entered its Reconstruction era. Listen to this podcast to learn what that entailed and who was affected.

Explore an interactive map of battles from the American Revolution, along with detailed summaries of each engagement

The Supreme Court has never definitively settled federal war powers

Despite more than two centuries of conflict over war powers, the Supreme Court has consistently avoided defining the precise boundary between congressional and executive authority, leaving that boundary to be contested by the political branches.

Ranchos were large land grants in California to Spanish, Mexican leading families

They were typically given to leading families or retired soldiers as means of settling the land with loyal people. The hundreds of ranchos have since shaped land-use policy in the area, determining plots of major cities and ranches today.

The Wrights’ patent battles delayed the development of aviation technology in the US

By the time World War I began in 1914, the US was lagging behind European powers in aviation. This stemmed primarily from wars over patents between the Wrights and competitor Glenn Curtiss. The pair argued their 1906 patent covered all mechanisms enabling lateral flight.

William Clark negotiated one-tenth of all ratified treaties between Native Americans and the US

After the expedition, Clark held key territorial and federal roles, overseeing western expansion and Native relations. While he expressed sympathy for displaced natives, he oversaw the transfer of millions of acres from Native nations to US control through various treaties.

Hamilton's tax on whiskey sparked the first armed rebellion against US federal authority

As Treasury secretary, Alexander Hamilton designed an excise tax on whiskey that provoked violent resistance in western Pennsylvania. The Whiskey Rebellion ended when George Washington mobilized state militias under federal authority to enforce the law.

The US war on drugs, explained

The United States has been fighting a global war on drugs for decades. By making drugs more expensive and less available, the US has sought to reduce drug use and inhibit the international drug trade. However, increasing prison populations,...

The power and influence of the American presidency have expanded significantly over time—far beyond what the founders envisioned.

Experimental hantavirus vaccines and therapies, still under development, have long been funded by the US military.

In 2025, four executives from large tech companies were given positions in the US Army Reserves—including Palantir Chief Technology Officer Shyam Sankar, which reinforced Palantir's ties with the US military and its role as a leading defense partner.

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

The concept of phantom limbs, the perception that amputated limbs are still present, dates back to a French military surgeon in the 16th century.

The United States has had a tumultuous relationship with Cuba since its 1959 revolution, highlighted by a nuclear crisis and a decades-long trade embargo.

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

The Russia-Ukraine conflict is the largest ground war in Europe since World War II in terms of casualties, forces mobilized, and displacement of civilians.

Abraham Lincoln was almost assassinated weeks before his inauguration as he traveled from Illinois to DC through Baltimore in 1861; it took two independent claims for Lincoln to be convinced the threat was real

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

Mark Twain spent decades feuding with the US Postal Service, convinced its costs and regulations were bureaucratic overreach.

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

20,000 letters to the advice columnist 'Dear Abby' provide insight into prevailing sex, religion, and LGBTQ fears, anxieties, and concerns from the 1950s onward.

Brandi Chastain, the star of the 1999 US victory over China in the 1999 Women's World Cup, was a last-second choice to take the penalty kick that sealed the victory.

Explore the known asteroids, comets, and spacecraft involved in asteroid studies within our solar system with 'Eyes on Asteroids,' a 3D visualization from NASA.

View the ten deadliest tornadoes in US history.

Fireworks make a loud booming sound after exploding due to air expanding faster than the speed of sound.

Fast-casual restaurant Chili's is experiencing a resurgence, with its parent company recently reporting a nearly 32% increase in sales, thanks to passionate Gen Z fans on TikTok.

Poison ivy's characteristic rash is caused by an allergic response to an oily compound in the plant called urushiol.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

A small portion of The Winstons' 'Amen, Brother,' an obscure '60s gospel record, is the basis for thousands of hip-hop tracks, making it one of the most sampled records ever that's informally known as 'the Amen break.'

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.