Five key causes of World War I

How WWI began with the assassination of Archduke Franz Ferdinand

World War I started for several reasons—imperialism, militarism, nationalism, and more—but the catalyst was the assassination of Archduke Franz Ferdinand and his wife Sophie, the Duchess of Hohenberg by the young assassin Gavrilo Princip. Read this article ton see how the assassination sparked the chain reaction that led to the Great War.

Who started WWI?

World War I started with the assassination of the Archduke Franz Ferdinand and his wife Sophie, Duchess of Hohenberg. That's certainly one of the biggest catalysts for the war, but who started it? Ten historians offer their interpretations of which nations bore the brunt of the responsibility. As this article unsurprisingly discovers, it's complicated.

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.

Everything you need to know about WWI

Summarizing World War I seems like an impossible task, but this article makes a great effort at providing a easily digested survey of the Great War. Read about WWI from the first shots fired by assassin Gavrilo Princip at the Archduke Franz Ferdinand and his wife Sophie, to the various campaigns waged by the war's participants, to the equipment provided to the various fighting forces.

Illustrating the beginning and end of WWI through maps

In August of 1914, Germany invaded an ostensibly neutral Belgium, kick-starting World War I. The war became one of the deadliest conflicts in human history, decimating Europe and reshaping global politics for the next century. It also brought forward sweeping and terrifying new military technologies, a product of the Industrial Revolution. Explore 40 maps explaining the Great War in detail.

An interactive timeline of the major events of World War I

World War I took place between July 28, 1914 and November 11, 1918, but a lot happened within that relatively short time. And even more occurred afterward. The comprehensive timeline shows when major and influential events took place during the conflict, accompanied by articles, videos, and other media in support.

How the Great Depression and end of WWI paved the way for Hitler's rise to power

The end of WWI was triggered by an armistice that blamed the conflict on Germany and required the financially struggling country to pay reparations. This outraged nationalists and ignited conspiracies that Hitler was able to capitalize on, according to this six-minute video. It was during this financial strain that the Great Depression hit.

A visual summary of WWI

This animated video summarizes the "Great War"—World War I—tracing its progression through Europe, detailing the rise of nationalism in the middle of the 19th century until the signing of the peace treaties after 1918. This 18-minute provides a year-to-year accounting of the war with various helpful insights along the way.

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.

The 1915 sinking of the Lusitania precipitated World War I

In 1915, the British RMS Lusitania sank after being torpedoed by a German submarine. The Germans claimed the ocean liner was transporting munitions. Almost 1,200 civilians were killed in the disaster, which became a symbol of German aggression in the lead-up to World War I.

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.

Was WWI really the first world war?

Was World War I the first true international conflict? This article thoroughly explores the meaning of the term world war. It also suggests a few previous conflicts, some of which involved battles in the Americas as well as Europe, that might have been more accurately described as a "world wars."

Who was impacted by the first world war, and how?

This interactive map from the National Archives in the UK details the global impact of World War I. Countries and territories from Aden to New Zealand were impacted by the Great War, which started in 1914 and lasted until 1918. By selecting various locations on the map, viewers can access articles and evidence on how the war's influence traveled far beyond the front lines.

Should the US have entered into World War I?

America entered World War I in 1917, but had remained neutral until that point. President Woodrow Wilson addressed Congress, further underlining the USA's neutrality. Eleven weeks later, he asked for a declaration of war. With attacks by German saboteurs on an American munitions depot, it seemed he had no choice. But did he? This article asks what might have happened if the US stayed out of WWI.

Exploring World War I technology on the battlefield

Industrialization brought massive changes to warfare during the Great War. Newly-invented killing machines begat novel defense mechanisms, which, in turn spurred the development of even deadlier technologies. Nearly every aspect of what we would consider modern warfare debuted on World War I battlefields. Starting with soldiers on horseback carrying lances and ending in poison gas, machine guns, and aerial battles, this gallery shows the first tools of modern warfare.

100 ways the Great War changed the world

What was the point of WWI? What impacts did it have? How has it influenced life today? Click through this Wall Street Journal photo gallery to find out.

A global interactive guide to the first world war

Using rarely seen films, new reports of the day, and interactive maps, 10 historians provide a summarized history of the Great War, World War I. During the course of this half hour film, get a variety of insights and perspectives on the so-called "war to end war" and its long-reaching effects.

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

Why wasn't German emperor Kaiser Wilhelm punished for starting WWI?

The accusations were explosive: a head of state had not only begun an illegal war, but egged his troops on to a series of horrific atrocities that left

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.

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.

Why were tanks invented?

Tanks first appeared in warfare in World War I. As old methods of conducting battles proved ineffective, the idea of an armored vehicle that could traverse almost any terrain and carry a cannon came to fruition. World War I provided the impetus and finances to develop the modern tank. Learn more in this short but detailed article.

The widespread violence of World War I birthed surrealism

Following World War I, artists used unconventional forms of expression to make sense of the death and destruction they'd witnessed for years. Life as they knew it had ended, and movements like Surrealism, founded by André Breton, rebelled against tradition.

Why did the Ottoman Empire violently target Armenians during WWI?

In anticipation of threatened Allied landings at the strategically important Gallipoli peninsula, Ottoman authorities arrested 240 Armenian leaders in Constantinople on April 24, 1915, and deported them east. This roundup is commemorated today by Armenians as the beginning of the genocide, according to this article.

How World War I ended in 2010

Germany made its final reparations-related payment for the Great War on Oct. 3, nearly 92 years after the country’s defeat by the Allies. What took Germany so long to pay for the war?

World War I brought attention to US reliance on mineral imports

Domestic stockpiles were inadequate for the extended trade disruptions caused by the four-year war. In response, the US Geological Survey increased its geological mapping to help search for important metals alongside new oil fields for fuel.

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.

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.

Timeline: the Middle East conflict

During the First World War, Western and Arab powers negotiated the future political status of Arab lands. Since WWI, a complex history of political, economic, and social events have fueled tension and violence between Israel and Palestine. This timeline, compiled by Al Jazeera, highlights important global events defining conflict in the Middle East from 1915 to 2007.

European leaders pursued appeasement of Hitler in the 1930s, hoping to avoid war.

What happened on WWI's Italian Front?

The battle in the Dolomites, or the White War, might have been the roughest, most arduous, and deadliest conflict during World War I. Italian and Austrian troops fought for control of the Dolomites mountain range over the course of three years, leading to the deaths of 700,000 Italian soldiers and 350,000 Austro-Hungarian troops. A grim account of a dirty little war high in the Dolomites.

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.

What impact did WWI have on the US civil rights movement?

One of the great hypocrisies in American history involve the expectation of African-Americans to defend liberty in several wars while being deprived of it when they returned home to, as this article puts it "disfranchisement, segregation, debt peonage and racial violence." The writer reflects on World War I and how it affected the fight for civil rights in the USA.

Franklin D. Roosevelt's 1941 speech framed World War II as a global fight for universal rights

Eleven months before the attack on Pearl Harbor, President Roosevelt outlined four fundamental freedoms that, in his words, people "everywhere in the world" ought to enjoy—speech, worship, freedom from want, and freedom from fear.

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.

The 10 main elements of fascism

This 10-minute video explains the 10 main elements of fascism, which it describes as the "cult of the leader" who promises national restoration that stymies the tide of a country's takeover by various groups. The main elements of fascism include...

Detailing the horrific conditions of life in the trenches

What was it like to live and fight in a trench during World War I? If you were on the German side you might have bunkers, electricity, and other basic comforts. If you were on the British and French side the conditions have been described as muddy and "horrific". Find out how unpleasant trench warfare was and how it affected WWI soldiers.

What would you have done on Armistice Day?

Armistice Day (now known as Veteran's Day in the United States), November 11, 1918, marked the end of hostilities on the Western Front of World War I. This collection of interactive videos and recordings of United Kingdom residents who fought in the war or supported those who did provides perspective on how individuals experienced that great day for themselves.

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.

Hitler declared war on the United States four days after Pearl Harbor

Despite having no treaty obligation to join Japan’s fight, Hitler declared war on the US on Dec. 11, 1941. The move pulled America into the European theater and is widely seen as one of Hitler’s most strategic blunders.

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.

Look through this WWI stretcher bearer's bag

While it was indeed the first industrialized war, medical science had yet to catch up on the battlefield. This nearly eight-minute video sorts through the contents of a World War I stretcher-bearer's satchel. A modern doctor and ex-officer assesses the bag's various medical tools for performing first aid on the battlefield.

The Great Depression was an international depression felt far beyond the US

Many countries suffered through a depression in the 1930s that the First World War, the US stock market crash, and an economic downturn in Germany turned into an international crisis.

The treaty's Article 5 requires mutual defense, but not necessarily military action.

Riveting artwork from the battlefields during World War I

During World War I, the United States government commissioned eight artists to accompany American Expeditionary Forces to Europe to sketch and document what they saw. Drawing tanks, soldiers, shattered villages, and even German prisoners of war, the artists preserved much of the war as a matter of historical record and to rally support back home.

Wish you could experience life on the Western Front of WWI?

Virtual reality offers a new perspective on World War I in this nearly 14-minute video. National WWI Museum and Memorial Public Program Specialist James Taub demonstrates the War Remains VR experience side by side with what he sees through the headset. A grim and detailed simulation of trench warfare combined with Taub's observations and insights.

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.

NATO's Article 5 has been invoked once—after 9/11

The article was invoked the day after the attacks and launched a series of NATO campaigns to fight global terrorism. This page includes excerpts from a speech by then-NATO Secretary General Jens Stoltenberg about the attacks and the organization’s response.

There were dozens of attempts to assassinate Hitler—most famously Operation Valkyrie in July 1944

Across his reign, Hitler survived at least 40 plotted and actual assassination attempts, ranging from lone actors in beer halls to organized military conspiracies. The most notable, Operation Valkyrie on July 20, 1944, led by Colonel Claus von Stauffenberg, planted a bomb at the Wolf’s Lair in an effort to kill Hitler and overthrow the Nazi regime. Though the explosion injured several, Hitler escaped with minor wounds, prompting a brutal purge of conspirators.

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.