The Partitions of Poland led to the erasure of the Polish-Lithuanian Commonwealth

Ukraine came under Russian imperial rule in the late 18th century

After centuries of division among neighboring powers, most of present-day Ukraine was absorbed into the Russian Empire by the late 1700s, marking the beginning of a long period of imperial control and cultural suppression.

Communist governments across Eastern Europe fell in 1989

In 1989, a series of mostly peaceful uprisings led to the collapse of communist regimes in Eastern Europe. Protests and political shifts in countries like Poland, East Germany and Czechoslovakia marked the end of Soviet dominance in the region.

Germany’s invasion of Poland in 1939 launched World War II

On September 1, 1939, Nazi Germany launched a surprise invasion of Poland using blitzkrieg—coordinated air bombardments and armored assaults—to overwhelm Polish defenses within weeks. This lightning-strike strategy shocked the world and signaled both the start of World War II and a revolutionary shift in modern military tactics.

How did China go from an empire to a republic?

In the 1800s, as China's economy was in flux, foreign imperialist powers began appearing on the horizon, leading China to lose land and influence in the region. This 48-minute podcast episode explores how this destabilization set the stage for the...

The failures of the interwar period made the case for a new international system

After World War I, countries devalued their currencies, raised tariffs to block imports, and seized territory unchecked, with the international community unable to organize effectively to stop them. The result was a global depression and, eventually, another world war.

Medieval Europe was a patchwork of hundreds of competing states

In the Middle Ages, Europe was divided into hundreds of kingdoms, duchies, and territories, bearing little resemblance to modern borders. This map captures the political landscape in 1444, as the Ottoman Empire was in the midst of its rise.

European powers carved up nearly all of Africa in just 4 decades

This video explains the "Scramble for Africa," when seven European nations seized over 90% of the continent between 1870 and 1910. Only Liberia and Ethiopia remained sovereign as imperial competition redrew Africa’s borders and reshaped its future.

How the British Empire transformed into today’s voluntary Commonwealth of Nations

This video explains how former British colonies—now independent states—evolved into the modern Commonwealth, a loose association representing nearly one-third of the world’s population. It traces the shift from imperial rule to a cooperative forum with no legal obligations to Britain or its monarch.

The western Roman Empire fell in the 5th century CE amid invasions, weakness

A mix of over-expansion, political instability, a weak military and economy, and the broad invasion of the Eurasian Huns prompted the downfall. Its eastern half, the Byzantine Empire, would last for another millennium.

The bizarre 1920 proposal to form a pizza-shaped central European state

In light of the challenges of the Treaty of Versailles, which concluded the Great War, a mostly unknown author, and son of the map's printer, PA Maas suggested central Europe be integrated into a single state. With a central capital in Vienna, 24 Kantons, or regions, would radiate outward in pie-slice shapes.

The Cold War (1947-1991) prompted the birth of NATO and the Soviet Warsaw Pact

The geopolitical rivalry between the United States and Soviet Union was considered “cold" because the two countries never directly engaged in military combat during the time period. This page from the Kennedy Presidential Library outlines the causes and major events of the early Cold War.

Wojtek the bear fought for Poland in World War II

Wojtek was a Syrian brown bear who eventually became a mascot, symbol, and eventually a soldier attached to the Polish II Corps during World War II. Learn about the amazing Wojtek, the Polish II Corps, and the incredible history of the Polish soldiers, many of whom had been imprisoned by the Germans or Soviets, who served during World War II.

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.

What led to the October Revolution?

The 1917 Russian Revolution is actually two separate revolutions. One happened that spring that ended centuries of Tsarist rule and led to the establishment of a provisional government. Another happened that autumn during which the Bolshevik...

The formation and breakup of Pangaea altered Earth’s geology and biodiversity

Coming from the Greek words for “all” (pan) and “Earth” (gaia), the supercontinent existed from about 320 million to 195 million years ago. The tectonic activity that split Pangaea into today’s continents may one day bring the continents back together, forming Pangaea Proxima.

Wealthy patricians and poorer plebeians struggled for power for centuries

During the Roman Republic, the plebs sought political protection, more access to power, and freedom, while the patricians looked to protect their elite status and wealth. Plebeians regularly "seceded," or effectively went on strike and did not fight for the patricians.

The Soviet Union consisted of 15 Soviet Socialist Republics

The USSR comprised 15 republics—Armenia, Azerbaijan, Belarus, Estonia, Georgia, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Moldova, Russia, Tajikistan, Turkmenistan, Ukraine, and Uzbekistan—all governed from Moscow, the Soviet capital and still Russia’s capital today.

The Dawes Act of 1887 broke up communally held tribal lands

Sometimes called the General Allotment Act, the Dawes Act divided reservation land into individual plots assigned to Native Americans, while "surplus" land was sold to white settlers. The policy led to Native tribes losing roughly 90 million acres, about two-thirds of their remaining land.

A podcast unpacking Pakistan’s political turmoil

Pakistan has been immersed in political crises for over 20 years. Despite being one of the world’s few nuclear powers, Pakistan’s internal instability has caused experts to question whether the country is, in fact, a failed state. Deep divisions...

Oktoberfest has been canceled 26 times

The first time, in 1813, Bavaria was fighting off Napoleon’s army, which left little time for celebration. Years were also lost to the Austro-Prussian War, a worldwide cholera outbreak, and both World Wars. Most recently, the 2020 and 2021 Oktoberfests were canceled due to COVID-19.

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.

How the Kingdom of Italy was unified in the 1860s

In 1861, in a process known as the Risorgimento, many of the traditional regions of Italy—like Sardinia, Lombardy, Parma, and Sicily—were unified within the Kingdom of Italy under King Victor Emmanuel II. This movement led to the national Italian identity as we know it today. This unity was opposed by the Pope, and Rome and Venetia remained outside the kingdom for some time.

Early American citizenship was defined inconsistently by individual states

The original US Constitution did not define national citizenship, leaving it to the states to apply their own rules. This led to inconsistent and often exclusionary standards across the country until after the Civil War.

...and allowed newly arrived European immigrants to maintain their cultures

19th-century public schools often included Protestant spiritual instruction, something that was disturbing for Catholic immigrants from Ireland, Italy, Poland, and elsewhere, who found homes in neighborhood “parochial” schools.

How royal panic led to Europe's deadliest witch hunts

This article delves into the witch "panics" and hunts that roiled across Scotland between 1590 and 1662. The witch hunts in Scotland were unusually deadly, with the country having five times the average European execution rate per capita. Their...

The United States is one of only around two dozen countries with a fully federal system of government, in which power is divided between national and state governments.

The original copy of the Declaration of Independence is not a pristine document, and even features a smudged anonymous handprint in the bottom left corner.

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

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.

Volcanic activity may have triggered the Black Death by spewing gases that led to crop failures in Europe, thus forcing the import of grain ships with plague-infested fleas.

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.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

Famed poet TS Eliot rejected the manuscript for George Orwell's political fable 'Animal Farm,' writing that its criticism of authoritarianism was not 'the right point of view.'

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

Coral polyps reproduce via broadcast spawning, where entire reefs simultaneously release reproductive cells for about one hour, once a year.

During the French Revolution, a botanist's letter asking about "dear Rhus" (poison ivy) was intercepted, leading authorities to suspect he was conspiring with the Russians.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

Recent research found that the brain doesn't seem to massively rewire following amputation—upending earlier beliefs about the cause of phantom limb pain.

Watch contemporary footage covering the US-backed Shah of Iran fleeing the country in the face of the 1979 Iranian Revolution

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

Walt Disney's early film 'Alice's Wonderland' was a groundbreaking innovation in the silent film era

Explore fun facts from the USPS, including unique post office buildings, a stamp that traveled past Pluto, and more.

Chaos theory—informally known as the butterfly effect—is the reason why weather forecasts are presented with probabilities rather than certainties.

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

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.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

The US first hosted the World Cup in 1994, a tournament that lives in soccer infamy for its poor planning and the murder of Colombian player Andres Escobar, who'd accidentally scored on his own net.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.