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

Post-WWII decolonization in Africa led to Cold War proxy conflicts

As newly independent African nations emerged after World War II, the US and USSR vied for influence—backing opposing sides in civil wars and revolutions. Conflicts in Angola, Ethiopia and Mozambique became proxy fronts in the Cold War.

The US and the USSR backed opposing sides in dozens of proxy wars during the Cold War

To avoid direct confrontation, the superpowers supported rival factions in conflicts around the world—including in Korea, Vietnam, Angola, and Afghanistan.

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 American Revolution became a template for a colonized world

The robust and radical transformation during the American Revolution created a template for dozens of future independence movements. Its key ideas of republicanism, individualism, and equality inspired revolutions in France, Haiti, Ireland, and more, paving the way for the broadly democratic world we know today.

The world reached historic levels of democracy under the rules-based order, though that trend has reversed

The share of democracies worldwide grew dramatically from the mid-20th century, reaching an all-time high in the early 2010s. Since then, the trend has reversed, with an increasing number of countries experiencing democratic backsliding.

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.

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.

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.

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.

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.

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 Stalin, Roosevelt, and Churchill shaped the postwar world

The Yalta Conference was a pivotal 1945 meeting between Allied leaders that helped shape the postwar global order and laid the groundwork for the founding of the United Nations.

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.

Britain's PM signaled the acceptance of African decolonization in 1960

This audio excerpt captures Harold Macmillan’s 1960 “Wind of Change” speech, in which he acknowledged rising African nationalism and declared that Britain would not resist decolonization—a pivotal moment signaling the Empire’s accelerating retreat from the continent.

Relationships between countries have become more peaceful since the rules-based order was established

Our World in Data monitors bilateral relationships on a spectrum from open rivalry to "positive peace"—deep cooperation and mutual protection. In 1945, no countries had highly cooperative security relationships. Today, nearly a fifth do.

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.

Explore 100 years of communism across the globe, from the 1917 October Revolution to North Korea's modern nuclear defiance.

After the USSR's fall, many experts believed liberal democracy had permanently prevailed

Political scientist Francis Fukuyama argued in 1992 that liberal democracy and market capitalism had defeated their ideological opponents and would eventually spread everywhere—a thesis he called "the end of history." Subsequent decades complicated that claim.

See an animated map of the entire Cold War.

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.

Much of the Global South responded to the Russia-Ukraine war by pursuing a strategy of 'active nonalignment'

Boston University scholar Jorge Heine suggests that countries across Africa, Asia, and Latin America are avoiding taking sides between Washington and Beijing—viewing the rules-based order as increasingly unresponsive to the needs of developing nations and considering the West's framing of the war irrelevant to its own interests.

Defining the use of 'Third World' in geopolitics

The term "Third World" is mostly out of use today for its limiting connotations, but in light of a reordering of geopolitical alliances amid the Ukraine war, historians are reevaluating the term's usefulness. Read the history of the term starting from the 1950s, and learn what several experts claim about its contemporary efficacy.

What led to the Vietnam War?

On the heels of gaining independence from colonizers, why did Vietnam fracture and begin its internal battle? Though the war took root during an independence movement against French colonial rule, it evolved into a Cold War confrontation with international support. This article explains six events that led to the conflict between North and South Vietnam.

Since World War II, formal declarations of war and peace treaties have become increasingly rare, replaced by cease-fires, authorizations of force, and "special military operations."

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.

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 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.

See how global nuclear arsenals surged—then shrank—by country since 1945

Worldwide nuclear stockpiles peaked at over 60,000 warheads in the mid‑1980s during the US-Soviet arms race. Today, about nine nations collectively maintain roughly 12,000 warheads, with Russia and the US still holding the majority.

Some colonies were centuries-old before they broke from Britain

The revolution did not happen overnight, but was a culmination of centuries of settlement, policies, and war in North America. This timeline provides key, fascinating events from the 1600s through the Revolution in a smooth, easy-to-read interface.

What Americans ate after WWII

Returning from World War II, the American cultural landscape saw a vast number of changes. Cuisine, in particular, diversified and modernized thanks to traveled soldiers and wartime innovation. From inventions like powdered cheese to the popularization of instant coffee and Chinese food, explore the changes to the American food industry that continue to influence what we consume today.

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 20th-century rise of fascism affected the World Cup

Spain, in the midst of a civil war, did not participate, and Japan, after invading China, pulled out of the competition. An additional six Central and North American teams scratched by the time that year's World Cup began.

The Soviet Union explained

From 1922 to 1991, the Soviet Union spanned one-sixth of Earth’s landmass and housed nearly 300 million people. As the most significant test of Marxist governance, it sat at the center of the century’s defining struggle between capitalism and communism.

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.

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.

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.'

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.

See what it was like to live in the United States during World War II

In America, life was transformed by total war: sixteen million service members left civilian life, while massive industrial production demanded labor. Women, minorities, and teens filled factories, fueling boomtown growth and breaking social barriers. Simultaneously, rationing, recycling drives, Victory Gardens, ration stamps, blackout drills, and war bond campaigns permeated daily routines.

A collection of contemporary maps from World War II

Newspapers published detailed maps of the conflict in real-time. See different portrayals of the situation, ranging from propaganda maps to speculative maps about the war's outcome. The fascinating depictions reveal how maps can show us the aspirations and intentions of different players in a global conflict.

Propaganda became a key weapon in the US–Soviet Cold War

Both superpowers waged a global battle for hearts and minds through propaganda—using film, radio, art and education to promote their values. The US emphasized freedom and prosperity, while the USSR championed socialism and anti-imperialism.

The formation of the UN elevated the US on the world stage

This podcast episode of "To the Best of My Ability" from the National WWII Museum goes behind the scenes of the United Nations' founding from the American perspective. It explores how FDR's vision for global peace took shape, how Truman carried it forward, and how Eleanor Roosevelt helped define human rights—set against the backdrop of wartime diplomacy, Cold War tensions, and the San Francisco Conference, where the UN Charter was signed.

How World War II affects your wallet today

The world's deadliest conflict also impacted social programs extensively, including ways that still affect your money today. World War II is responsible for the practice of employers withholding tax payments and sponsoring health insurance, as well as the norm of providing school lunches for the nation's schoolchildren. Watch this brief video to learn more.

European colonization contributed to coffee's spread

European colonization created channels for large-scale coffee exports with workforces based in Asia, Latin America and the Caribbean. Trade routes throughout the Middle East and the rest of the world carried the drink to new shores and changed the agricultural and economic landscapes of the countries in the Bean Belt.

Hear how the world reacted to the American Civil War

European nations closely watched the Civil War for its economic and political consequences. Some European nations quietly engaged diplomatically with the Confederacy but withheld recognition. When the Union made slavery's abolition a central cause, European public opinion turned sharply against the South.

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.

Japan's imperial expansion in Asia in the 1930s set the stage for war with the US.

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More than 58,000 American soldiers died in the Vietnam War

Fought to contain communism in Southeast Asia, the Vietnam War became one of the most costly and controversial Cold War conflicts. The US ultimately withdrew in 1973, and South Vietnam fell to communist forces two years later.

The Truman Doctrine marked the start of US containment strategy

Introduced in 1947, the Truman Doctrine pledged US support for nations resisting communism—starting with Greece and Turkey—and launched the containment policy that defined early Cold War strategy.

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.

The United Nations was founded in San Francisco in 1945.