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.

Soviet control spread across Eastern Europe after WWII

In the late 1940s, the USSR solidified control over Eastern Europe by installing pro-communist regimes in countries like Poland, Hungary and Romania—often through rigged elections and political repression.

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 Berlin Wall physically separated East and West Berlin for nearly three decades, preventing East Germans from fleeing to the West and earning the nickname 'the Iron Curtain.'

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.

Explore a map of Medieval Europe, which was a patchwork of hundreds of competing states.

The Concert of Europe's collapse contributed to World War I

The 19th-century great power system gradually unraveled due to rising nationalism, imperial rivalry, and shifting alliances—leading to its collapse in 1914 and the outbreak of the deadliest war the world had yet seen.

World War I causes

World War I was, as the name says, truly war on the global scale. Fought between the French, Russian, British, Austria-Hungary, Ottoman, and Russian Empires, it was in part, a battle for territory. And after the war ended, several of these empires collapsed. Explore the different causes of World War II in this article.

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.

The world rapidly decolonized after World War II, with roughly a hundred new countries emerging between 1945 and 1989.

Decolonization isn't complete, as nearly 2 million people were living in UN-designated non-self-governing territories as of 2023.

The Soviet Union collapsed in 1991, due to economic decline and political unrest

By the late 1980s, the Soviet economy was stagnating and its political system was under tremendous strain. Soviet reforms failed to reverse the decline, and growing independence movements led to the USSR’s formal dissolution in 1991.

The Russian Revolution toppled the tsar and brought the Bolsheviks to power

In 1917, mass unrest, war exhaustion, and economic collapse overthrew the Romanov monarchy, enabling the Bolsheviks to seize control. The revolution dismantled imperial Russia and set the foundation for the creation of the Soviet Union.

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.

Some experts argue that Russia was never effectively integrated into the rules-based order after 1991

This piece argues that Russia's difficult relationship with the IMF and World Bank in the 1990s—characterized by economic shocks and perceived Western condescension—helped shape Moscow's later hostility toward the liberal order.

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.

Many countries remained neutral after Russia's invasion of Ukraine

Following Russia's 2022 invasion of Ukraine, few nations outside the West imposed sanctions on Moscow. Major powers such as China, India, Brazil, and Turkey remained neutral, underscoring global divisions over how to confront Russian aggression.

During the Cold War, the rules-based order was largely limited to the West

The Soviet Union and its allies operated outside the Bretton Woods institutions, meaning the postwar liberal order functioned as a regional rather than a truly global system. This changed with the USSR's collapse in 1991.

Wartime conferences exposed cracks in the US–Soviet alliance

At the Tehran, Yalta and Potsdam Conferences, Allied leaders coordinated WWII strategy—but deep disagreements over postwar Europe foreshadowed the Cold War. The USSR’s push for influence in Eastern Europe clashed with US and British calls for self-determination.

Kyivan Rus laid the cultural foundations for Eastern Europe

From the 9th to the 13th centuries, Kyivan Rus was a powerful East Slavic state centered in Kyiv. It shaped the region's language, religion, and political traditions—forming the shared cultural roots of modern-day Ukraine, Russia, and Belarus.

Mapping Russia's historical borders

This interactive map illustrates how the country’s borders have changed over the centuries, dating all the way back to the year 862, when the Varangian king Rurik assumed leadership of Ancient Rus. Scroll down to see how Russia vastly expanded its territory in the 16th and 17th centuries, and skip to 1991 to see which countries gained independence after the fall of the USSR.

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.

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.

Ukrainian nationalism rose under imperial repression

In the 19th century, Ukrainian nationalism took shape through cultural revival movements and intellectual circles—even as the Russian Empire banned the Ukrainian language and sought to suppress Ukrainian identity.

The treaty that ended the First World War laid the groundwork for the Second.

How failures at Versailles Conference led to more racial inequality

Suffering a pandemic and the aftermath of a war that killed 50 million, the world in 1920 faced a turning point as it negotiated a new political order. As today, the key issue was racial inequality.

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.

The Nazis and Soviets agreed to a non‑aggression pact in 1939

On August 23, 1939, Nazi Germany and the Soviet Union signed the Molotov–Ribbentrop Pact—a public commitment to not attack each other combined with a secret agreement dividing Eastern Europe into spheres of influence. This pact enabled Germany to invade Poland unopposed from the east and delayed conflict with the USSR until June 1941.

The Middle Ages, the roughly 1,000-year period between the fall of Rome and the Renaissance, shaped the political and cultural foundations of modern Europe.

Watch the British Empire expand and recede over 5 centuries

This interactive map traces the British Empire from 1450 to today—showing its explosive 19th-century expansion to one-quarter of the world's land and its steady contraction after World War II.

Proponents argue that abandoning the rules-based order risks a return to the chaos that led to 2 world wars

Brookings scholar Robert Kagan warns that if China and Russia gain regional dominance, the world could return to the unstable conditions of the late 19th century—the same chaos that led to two devastating world wars.

Putin claimed the invasion of Ukraine was to demilitarize and 'denazify' the country

In a 5,000-word historical treatise he wrote himself, President Vladimir Putin claimed the move was meant to restore Russia's historic lands. Many Western historians and global leaders described these narratives as false pretexts for aggression.

The Concert of Europe was an earlier attempt to manage great power relations through shared rules

After the Napoleonic wars, European powers established a system of regular consultation to manage conflicts and maintain the balance of power. It offered relative stability for nearly a century before deteriorating.

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.

A small island nation built the largest empire in history

See how Britain grew from a small kingdom into a global empire ruling nearly a third of the world, then unraveled through war, nationalist movements, and declining power—leaving just 14 overseas territories as remnants of its once-vast domain.

The world is shifting from unipolarity toward a multipolar order

The post-Cold War world was briefly unipolar after 1991, with the US standing alone as a global superpower following decades of US-Soviet bipolarity. Analysts increasingly describe today's order as multipolar, with China, Russia, the US, and regional powers all competing for influence.

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...

Ukraine's Soviet Republic was tightly bound to Moscow's control

Proclaimed in 1917 and absorbed into the USSR in 1922, the Ukrainian Soviet Socialist Republic was nominally independent yet operated under Moscow's control, with its government and laws directed by the Soviet Communist Party.

Ukraine became independent after the Soviet Union's collapse

Ukraine declared independence on Aug. 24, 1991, following the dissolution of the Soviet Union. In a national referendum, over 90% of Ukrainians approved independence, establishing a democratic constitution and marking the birth of a modern sovereign state.

In communist Poland, the VHS black market provided a window into the US

Although government censors often banned official releases, Polish residents enjoyed a healthy black market of stores and traders, who offered all the latest Hollywood movies.

The Revolution split the Iroquois Confederacy, as members allied with different sides.

The 1955 Warsaw Pact was the Soviet Union’s answer to NATO

The pact included Albania, Bulgaria, Czechoslovakia, East Germany, Hungary, Poland, Romania, and the USSR. The pact established collective security and a joint military command between the member countries.

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.

Economic stagnation and the arms race pushed the USSR toward collapse

By the 1980s, chronic economic stagnation and soaring military costs forced Gorbachev to launch sweeping reforms—perestroika and glasnost—to revive the Soviet system. Instead, openness fueled independence movements across the republics, accelerating the regime’s rapid downfall.

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 Romanov family ruled Russia for more than 300 years

From 1613 to 1917, 18 Romanovs—including Peter and Catherine the Great—governed the vast Russian Empire. Their dynasty ended abruptly in 1917 when Nicholas II abdicated amid wartime shortages and revolutionary unrest, marking the end of imperial Russia.

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.

Colonial self-rule fostered strong autonomy and distrust of centralized power

American colonies were governed through a patchwork of different systems, ranging from Crown-run to locally controlled. Broad local autonomy—often followed by sudden imperial crackdowns—taught colonial leaders to prize home rule and distrust distant centralized power, attitudes that later informed US federalism.