World War I, also known as the Great War, was a global conflict that lasted from 1914 to 1918.
1 It
involved most of the world's great powers,2 assembled in two opposing alliances: the Allies and the
Central Powers.3 The war was unprecedented in its scale, the number of casualties, and its impact
on the 20th century.4
Background: The World Before the War
The early 20th century was a time of great change and tension in Europe. 5 Many countries were
powerful and rich because of their industries and the lands they controlled in other parts of the world
(colonies).6 This period is often called the "Age of Imperialism."
Rising Powers and Old Empires
Countries like Great Britain and France had large empires.7 But new powers were rising. Germany,
unified in 1871, was quickly becoming a strong industrial and military nation. 8 It wanted its "place in
the sun," meaning it desired more colonies and influence, just like Britain and France.9 This ambition
caused nervousness among the older powers.
Other empires, like the Austro-Hungarian Empire (ruling over many different groups of people in
Central Europe) and the Ottoman Empire (a long-standing power in the Middle East, but growing
weaker), were facing internal problems.10 Many smaller groups within these empires wanted to have
their own independent countries. This desire for self-rule is called nationalism. Prominent historian
Eric Hobsbawm noted that nationalism was a powerful force that could bind people together but
also create deep divisions and rivalries between nations.
A Web of Alliances
To protect themselves, countries started making agreements, or alliances. If one country in an
alliance was attacked, the others promised to help.11 By 1914, there were two major alliance systems:
● The Triple Alliance: Germany, Austria-Hungary, and Italy (though Italy would later switch sides).
● The Triple Entente: France, Russia, and Great Britain.12
Historian Margaret MacMillan, in her book "The War That Ended Peace," argues that these
alliances, meant to keep peace, actually made a large war more likely. If a small conflict started
between two countries from opposing alliances, it could quickly pull all the other allied countries into
the fight.
The Arms Race
As tensions grew, major European powers began to build up their armies and navies.13 This was called
an arms race. Germany, in particular, expanded its navy to challenge Great Britain’s powerful fleet.
This military build-up created an atmosphere of suspicion and fear.14 If countries had big armies,
they might be more tempted to use them. Scholar David Stevenson has extensively documented
the naval race between Germany and Britain, highlighting it as a significant factor in pre-war
tensions.
Historiographical Debate: Who Was to Blame?
Historiography means the study of how history is written. For World War I, historians have debated
for a long time about who or what was mainly responsible for starting the war.
The "German Guilt" Thesis
Right after the war, the Treaty of Versailles, which officially ended the war, declared that Germany
and its allies were responsible for all the loss and damage.15 This is known as the "War Guilt Clause."
Many early historians, especially in the Allied countries, agreed with this. They pointed to Germany's
ambition and its aggressive actions.
German historian Fritz Fischer in the 1960s famously argued that Germany did have a plan for
expansion and deliberately risked war to achieve its aims.16 He based his arguments on newly
discovered German government documents. This view caused a lot of debate, especially in Germany.
A Shared Responsibility?
Later, many historians began to argue that the causes were more complex and that blame should
be shared among all the major powers. They pointed to the rigid alliance systems, the arms race,
intense nationalism, and the mistakes made by leaders in the summer of 1914.17
Christopher Clark, in his book "The Sleepwalkers: How Europe Went to War in 1914," suggests that
the leaders of all the European powers were like "sleepwalkers," unaware of the terrible
consequences of their decisions.18 He argues that no single country was solely to blame, but rather
a collective failure of statesmanship led to the catastrophe.
The Role of Imperialism and Capitalism
Some historians, often influenced by Marxist ideas, like Vladimir Lenin in his work "Imperialism, the
Highest Stage of Capitalism," argued that the war was an inevitable result of competition between
capitalist countries for colonies and resources. While this view is less dominant today as a sole
explanation, the economic rivalries of the era are still considered an important background factor by
many.
The debate continues, but most historians today accept that World War I was caused by a complex
mix of long-term underlying factors and short-term decisions made by political and military leaders.
The Causes: Why Did It Happen?
There wasn't just one single reason for the war. It was like a pile of dry wood waiting for a spark.
M.A.N.I.A - A Simple Way to Remember
A common way to remember the main long-term causes is the acronym M.A.N.I.A:
● Militarism: This refers to the build-up of armies and navies and the belief that a country should
have a strong military to protect its interests and be ready to use it.19 As historian A.J.P. Taylor
argued, the detailed war plans and mobilization timetables, particularly Germany's Schlieffen
Plan (a plan to quickly defeat France before turning to fight Russia), created a situation where
once mobilization began, it was very hard to stop the slide into war.
● Alliances: As mentioned earlier, the system of secret and open alliances (Triple Alliance and
Triple Entente) meant that a conflict between two nations could quickly draw in many others. 20
If Austria-Hungary attacked Serbia, Russia (Serbia's ally) would likely step in, which would then
bring Germany (Austria-Hungary's ally) and France (Russia's ally) into the conflict.21
● Nationalism: This was an intense pride and loyalty to one's own country.22 While it could unite
people within a nation, it also created rivalry and hatred between nations. 23 Different ethnic
groups in empires like Austria-Hungary wanted their own independent nations (e.g., Serbs,
Croats, Czechs).24 Serbian nationalism, in particular, played a direct role in the spark that ignited
the war.25 Margaret MacMillan emphasizes how nationalist assumptions and the belief in
national superiority fueled the willingness to go to war.
● Imperialism: This is when powerful countries try to control weaker countries or regions to gain
resources, markets, and prestige.26 European powers competed fiercely for colonies in Africa
and Asia.27 This competition led to tension and mistrust between them.28 For instance, Germany's
desire for a larger colonial empire clashed with the established empires of Britain and France.
● Assassination (The Spark): This was the immediate cause of the war.29
The Spark: The Assassination in Sarajevo
On June 28, 1914, Archduke Franz Ferdinand, the heir to the throne of Austria-Hungary, was visiting
Sarajevo, the capital of Bosnia.30 Bosnia was a region annexed by Austria-Hungary, but many Serbs
living there and in neighboring Serbia wanted Bosnia to be part of a "Greater Serbia."31 A Serbian
nationalist group called the "Black Hand" planned to assassinate the Archduke. 32
A young Serbian nationalist named Gavrilo Princip shot and killed Archduke Franz Ferdinand and
his wife, Sophie.33
The July Crisis: How the Spark Led to Fire
Austria-Hungary was furious and blamed Serbia for the assassination.34 They saw it as an opportunity
to deal with Serbia once and for all.
1. Austria-Hungary's Ultimatum: Supported by Germany (which gave Austria-Hungary a "blank
cheque," meaning full support), Austria-Hungary sent Serbia a very harsh list of demands, called
an ultimatum, on July 23, 1914.35 They knew Serbia would likely not agree to all of them. Historian
Samuel R. Williamson Jr. has argued that Austria-Hungary was determined to go to war with
Serbia, regardless of the Serbian response.
2. Serbia's Response: Serbia agreed to most of the demands but not all of them.
3. Declaration of War: On July 28, 1914, Austria-Hungary declared war on Serbia.36
4. Mobilization: Russia, as Serbia's ally, started to mobilize its army (get it ready for war) to
support Serbia.37
5. Germany's Reaction: Germany saw Russia's mobilization as a threat and declared war on
Russia on August 1, 1914.38 It also declared war on France (Russia's ally) on August 3.
6. Invasion of Belgium: Germany's war plan (the Schlieffen Plan) involved attacking France by
going through neutral Belgium.39 When German troops entered Belgium on August 4, Great
Britain, which had promised to protect Belgium's neutrality, declared war on Germany.
And so, the "Great War" began. Many people initially thought it would be over by Christmas. They
were tragically wrong.
The Events in World War I: What Happened?
The war was fought on several fronts (areas where fighting takes place) across Europe, the Middle
East, Africa, and Asia.40 It involved new technologies and brutal tactics that led to enormous
casualties.41
The Western Front: Stalemate and Trenches
● Early German Advances: Germany initially advanced quickly through Belgium and into France,
hoping for a swift victory.42
● The Battle of the Marne (1914):43 However, the French and British forces managed to stop the
German advance at the Battle of the Marne, near Paris.44
● Trench Warfare: After the Battle of the Marne, both sides dug long lines of trenches, stretching
from the North Sea to the Swiss border.45 For the next four years, the Western Front was largely
a stalemate, with neither side able to achieve a decisive breakthrough.46 Soldiers lived in terrible
conditions in these trenches – cold, wet, muddy, and surrounded by disease and death.47 John
Keegan, a renowned military historian, vividly described the horrors and futility of trench
warfare in his book "The Face of Battle."48
● Major Battles: Huge battles, like the Battle of Verdun (1916) and the Battle of the Somme (1916),
resulted in hundreds of thousands of casualties but gained very little ground. 49 New weapons
like machine guns, heavy artillery, poison gas, and tanks were used, making the fighting even
more deadly.50 The Battle of Passchendaele (1917) became infamous for its horrific conditions
and massive loss of life for minimal gains.51
The Eastern Front: More Movement, But Still Brutal
● Russia vs. Germany and Austria-Hungary: The Eastern Front was fought mainly between
Russia on one side and Germany and Austria-Hungary on the other. It was much larger than the
Western Front, and the fighting was more mobile, with less trench warfare. 52
● Early Russian Successes and Later Defeats: Russia initially had some successes against
Austria-Hungary but suffered heavy defeats against the more industrialized German army, such
as at the Battle of Tannenberg (1914).53
● The Russian Revolution (1917): By 1917, Russia was exhausted by the war.54 There were
massive casualties, food shortages, and discontent among the people.55 This led to the Russian
Revolution. The Tsar (Russia's emperor) was overthrown, and eventually, the Bolsheviks
(Communists) led by Vladimir Lenin seized power.56
● Russia Exits the War: The new Bolshevik government signed the Treaty of Brest-Litovsk with
Germany in March 1918, pulling Russia out of the war.57 This allowed Germany to move many of
its troops from the Eastern Front to the Western Front. Historian Richard Pipes extensively
covered the link between the war's strains and the collapse of the Tsarist regime.
Other Fronts
● The Italian Front: Italy joined the Allies in 1915, hoping to gain territory from Austria-Hungary.
Fighting took place in the mountainous terrain of the Alps. The Battle of Caporetto (1917) was a
major defeat for the Italians.58
● The Gallipoli Campaign (1915-1916): The Allies (mainly British, Australian, and New Zealand
troops – ANZACs) tried to attack the Ottoman Empire (which had joined the Central Powers) at
Gallipoli, aiming to open a sea route to Russia and knock the Ottomans out of the war. 59 The
campaign was a disaster for the Allies, with heavy casualties and an eventual withdrawal.
● The Middle Eastern Front: Fighting also occurred in Mesopotamia (modern-day Iraq),
Palestine, and the Arabian Peninsula between the British (often aided by Arab nationalists) and
the Ottoman Empire.60 Figures like T.E. Lawrence ("Lawrence of Arabia") played a role in
encouraging Arab revolts against Ottoman rule.61
● War at Sea: Great Britain used its powerful navy to blockade Germany, preventing supplies from
reaching it.62 Germany, in turn, used submarines (U-boats) to attack Allied shipping. German U-
boat attacks on civilian ships, like the sinking of the Lusitania in 1915 (which killed many
Americans), angered the United States.63 Germany's decision to resume unrestricted submarine
warfare in 1917 was a key reason for the US entering the war.64
● War in the Air: Airplanes were used for the first time in a major war, initially for reconnaissance
(scouting) and later for bombing and air-to-air combat ("dogfights").65 Famous "ace" pilots
emerged, but air power did not play a decisive role in the outcome of the war. 66
The United States Enters the War (1917)
For the first few years of the war, the United States remained neutral, though it did supply the Allies
with food and weapons.67 Several factors led to the US declaring war on Germany in April 1917:
● Unrestricted Submarine Warfare: Germany's U-boats were sinking American ships.68
● The Zimmermann Telegram: A secret message from Germany to Mexico was intercepted.69
Germany proposed that Mexico join the war against the US, and in return, Germany would help
Mexico regain lost territories (Texas, New Mexico, Arizona).70 This outraged American public
opinion.
● Economic Ties: The US had strong economic ties to the Allies.71
● Desire to "Make the World Safe for Democracy": President Woodrow Wilson wanted the US
to play a role in shaping the post-war world.72
The arrival of fresh American troops and resources gave a significant boost to the Allied war effort
at a time when the other Allied nations were exhausted. Scholar Arthur S. Link, a leading biographer
of Woodrow Wilson, detailed the complex decision-making process that led America into the war.73
The End of the War
● German Spring Offensive (1918):74 With Russia out of the war, Germany launched a massive
offensive on the Western Front in the spring of 1918, hoping to win the war before too many
American troops arrived.75 They made some initial gains but were eventually pushed back.
● Allied Counter-Offensive (Hundred Days Offensive): The Allies, now strengthened by
American forces and using new tactics with tanks and aircraft, launched a series of successful
counter-offensives starting in August 1918.76
● Collapse of the Central Powers: The German army was pushed back, and its allies began to
collapse.77 Bulgaria surrendered in September, the Ottoman Empire in October, and Austria-
Hungary in early November.78
● Kiel Mutiny and German Revolution: In Germany, sailors mutinied (rebelled) in Kiel, and
revolution spread across the country.79 The German Emperor, Kaiser Wilhelm II, abdicated (gave
up his throne) and fled to the Netherlands.80
● Armistice: On November 11, 1918, at 11:00 a.m., Germany signed an armistice (an agreement to
stop fighting) with the Allies.81 The war was over.
Consequences, Impact, and Result
World War I was a turning point in history. It had profound and lasting consequences that shaped
the 20th century.82
Human Cost
● Millions Dead and Wounded: Around 8.5 to 10 million soldiers were killed, and over 20 million
were wounded. Millions of civilians also died due to war-related causes like starvation, disease,
and massacres.83 Historian Niall Ferguson in "The Pity of War" controversially argued that
Britain's entry into the war was a catastrophic error that magnified its scale and cost. 84
● The "Lost Generation": Many of the dead were young men, leading to a "lost generation" in
many countries. This had a deep psychological and social impact.
● Spanish Flu Pandemic (1918-1919):85 A devastating influenza pandemic, possibly spread more
easily by wartime conditions and troop movements, killed an estimated 50 million people
worldwide, further adding to the suffering.
Political Changes
● Collapse of Empires: Four major empires collapsed:86
○ The German Empire (replaced by the Weimar Republic)87
○ The Austro-Hungarian Empire (broken up into several new countries like Austria, Hungary,
Czechoslovakia, and Yugoslavia)88
○ The Ottoman Empire (eventually replaced by modern Turkey and other nations in the Middle
East)89
○ The Russian Empire (replaced by the Soviet Union after the revolution and civil war)90
● New Nations: Many new countries were created in Central and Eastern Europe, based on the
principle of national self-determination (the idea that people should be able to choose their
own government and form their own nation).91 This was championed by US President Woodrow
Wilson. However, the new borders often created new ethnic tensions.92
● Rise of Communism: The war led to the rise of the first Communist state in Russia (the Soviet
Union), which would have a major impact on global politics for the rest of the century.
● Shift in Global Power: The United States emerged from the war as a major world power, both
economically and politically.93 The traditional European powers were weakened.
Economic Impact
● Huge Debts and Economic Disruption: Countries had borrowed massive amounts of money
to pay for the war.94 The war also destroyed factories, farms, and infrastructure. This led to
economic instability and inflation in many countries. John Maynard Keynes, a prominent
economist who attended the Paris Peace Conference, strongly criticized the heavy financial
reparations demanded from Germany in his book "The Economic Consequences of the Peace,"
arguing they would lead to future instability.95
● Reparations: Germany was forced to pay huge sums of money (reparations) to the Allies for
war damages, which crippled its economy.96
● Disruption of World Trade: Global trade patterns were severely disrupted.97
Social Changes
● Changes in Women's Roles: With millions of men away fighting, women took on new roles in
factories, offices, and on farms.98 This contributed to the movement for women's suffrage (the
right to vote), which was granted in several countries after the war.99
● Increased Government Power: Governments took on greater control over their economies and
societies during the war (e.g., rationing, propaganda).100 Some of these powers remained after
the war.
● Psychological Impact: The horrors of the war led to widespread disillusionment, cynicism, and
a questioning of traditional values and authorities.101 This was reflected in art, literature, and
philosophy (e.g., the "Lost Generation" writers).102
The Treaty of Versailles (1919)
● Peace Settlement: The war officially ended with the signing of several treaties, the most
important being the Treaty of Versailles with Germany.103
● Key Terms for Germany:
○ War Guilt Clause (Article 231): Germany had to accept full blame for starting the war.104
○ Reparations: Germany had to pay massive reparations to the Allies.105
○ Territorial Losses: Germany lost territory to France (Alsace-Lorraine), Poland, Belgium, and
Denmark.106 Its colonies were taken away.107
○ Military Restrictions: Germany's army and navy were severely limited, and it was forbidden
to have an air force or submarines.108 The Rhineland (an area of Germany bordering France)
was demilitarized.
● Criticism of the Treaty: Many historians, like Keynes and later A.J.P. Taylor, argued that the
Treaty of Versailles was too harsh on Germany and sowed the seeds for future conflict. It
created resentment in Germany and contributed to the rise of extremist groups like the Nazis.109
Others, however, have argued that it was not as harsh as the treaties Germany imposed on
Russia (Brest-Litovsk) or Romania, or that Germany itself would have imposed had it won.
Margaret MacMillan in "Paris 1919: Six Months That Changed the World" provides a more
nuanced view, acknowledging the immense pressures and conflicting aims of the
peacemakers.110
The League of Nations
● An Idea for Peace: As part of President Wilson's "Fourteen Points" (his plan for a peaceful
world), an international organization called the League of Nations was established.111 Its main
goal was to prevent future wars through diplomacy, collective security (where member states
would help each other if attacked), and disarmament.
● Weaknesses: However, the League of Nations had serious weaknesses:
○ The United States, whose President had championed the idea, never joined (the US Senate
refused to ratify the treaty).112
○ Germany and Soviet Russia were initially excluded.
○ The League had no army of its own and relied on its members to enforce its decisions, which
they were often unwilling to do.113
○ It failed to prevent aggression by countries like Japan, Italy, and Germany in the 1930s. 114
Long-Term Result: Paving the Way for World War II
While World War I was called "the war to end all wars," it sadly did not. Many historians believe that
the unresolved issues, the harshness of the Treaty of Versailles, the economic turmoil, the rise of
aggressive ideologies (like Fascism in Italy and Nazism in Germany), and the failure of the League of
Nations all contributed to the outbreak of World War II just over two decades later in 1939.115 Scholar
E. H. Carr in "The Twenty Years' Crisis" argued that the international order established after WWI
was fundamentally flawed, leading to the subsequent conflict.116
World War I fundamentally reshaped the political, economic, social, and cultural landscape of the
world.117 It ushered in an era of greater instability and conflict, but also new ideas and movements
that would define the rest of the 20th century. Its legacy is still felt today in the borders of many
countries, the nature of international relations, and our understanding of the devastating potential
of modern warfare.118
