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World War I
Article Talk

Several terms redirect here. For other uses,

see WWI (disambiguation), The First World
War (disambiguation), World War One
(disambiguation), and Great War
(disambiguation).

World War I[b] or the First World War

(28 July 1914 – 11 November 1918),
also known as the Great War, was a
global conflict between two coalitions:
the Allies (or Entente) and the Central
Powers. Fighting took place mainly in
Europe and the Middle East, as well as
in parts of Africa and the Asia-Pacific,
and in Europe was characterised by
trench warfare; the widespread use of
artillery, machine guns, and chemical
weapons (gas); and the introductions
of tanks and aircraft. World War I was
one of the deadliest conflicts in
history, resulting in an estimated 10
million military dead and more than 20
million wounded, plus some 10 million
civilian dead from causes including
genocide. The movement of large
numbers of people was a major factor
in the deadly Spanish flu pandemic.

World War I

From top to bottom, left to right:

French attack from a trench at the Battle
of Verdun, 1916 · British artillery in action
at the Battle of the Somme, 1916 · U.S.
troops and Renault FT tanks during the
Hundred Days Offensive, 1918 · British
Vickers machine gun crew wearing gas
masks during the Battle of the Somme,
1916 · Ottoman Arab camel corps leaving
for the Middle Eastern front, 1916 ·
Aftermath of the Russian siege of
Przemyśl in Austria-Hungary, 1915

Date 28 July 1914 – 11

November 1918
(4 years, 3 months and
14 days)

Location Europe · Middle East ·

Africa · Pacific · Atlantic
· Mediterranean and
Adriatic

Result Allied Powers victory

(see Aftermath of World
War I)

Territorial Partition of the

changes Ottoman Empire,
dissolution of
Austria-Hungary,
transfer of German
colonies and
territories to other
countries

Formation of new
countries in Europe
and the Middle East,
such as Poland,
Yugoslavia, Weimar
Germany, Soviet
Russia and Soviet
Union, Lithuania,
Estonia, Latvia,
Austria, Hungary,
Czechoslovakia,
Turkey, Hejaz, and
Yemen

Belligerents

Allied Powers: Central Powers:

France German Empire
United Kingdom Austria-
and Empire: [show] Hungary
Russia[a] Ottoman
Italy (from Empire
1915) Bulgaria (from
United States 1915)
(from 1917) and others ...
Japan
and others ...

Commanders and leaders

See Main Allied See Main Central

leaders leaders

Casualties and losses

Military dead: Military dead:

Over 5,525,000 Over 4,386,000
Civilian dead: Civilian dead:
Over 4,000,000 Over 3,700,000
Total dead: Total dead:
Over 9,000,000 Over 8,000,000
...further details ...further details

The causes of World War I included the

rise of Germany and decline of the
Ottoman Empire, which disturbed the
long-standing balance of power in
Europe, and rising economic
competition between nations driven by
industrialisation and imperialism.
Growing tensions between the great
powers and in the Balkans reached a
breaking point on 28 June 1914, when
Gavrilo Princip, a Bosnian Serb,
assassinated the heir to the Austro-
Hungarian throne. Austria-Hungary
blamed Serbia, and declared war on
28 July. After Russia mobilised in
Serbia's defence, Germany declared
war on Russia and France, who had an
alliance. The United Kingdom entered
after Germany invaded Belgium, and
the Ottomans joined the Central
Powers in November. Germany's
strategy in 1914 was to quickly defeat
France then transfer its forces to the
east, but its advance was halted in
September, and by the end of the year
the Western Front consisted of a near-
continuous line of trenches from the
English Channel to Switzerland. The
Eastern Front was more dynamic, but
neither side gained a decisive
advantage, despite costly offensives.
Italy, Bulgaria, Romania, Greece and
others joined in from 1915 onward.

Major battles, including at Verdun, the

Somme, and Passchendaele, failed to
break the stalemate on the Western
Front. In April 1917, the United States
joined the Allies after Germany
resumed unrestricted submarine
warfare against Atlantic shipping.
Later that year, the Bolsheviks seized
power in Russia in the October
Revolution; Soviet Russia signed an
armistice with the Central Powers in
December, followed by a separate
peace in March 1918. That month,
Germany launched a spring offensive
in the west, which despite initial
successes left the German Army
exhausted and demoralised. The Allied
Hundred Days Offensive beginning in
August 1918 caused a collapse of the
German front line. Following the
Vardar Offensive, Bulgaria signed an
armistice in late September. By early
November, the Ottoman Empire and
Austria-Hungary had each signed
armistices with the Allies, leaving
Germany isolated. Facing a revolution
at home, Kaiser Wilhelm II abdicated
on 9 November, and the war ended
with the Armistice of 11 November
1918.

The Paris Peace Conference of 1919–

1920 imposed settlements on the
defeated powers, most notably the
Treaty of Versailles, by which Germany
lost significant territories, was
disarmed, and was required to pay
large war reparations to the Allies. The
dissolution of the Russian, German,
Austro-Hungarian, and Ottoman
Empires redrew national boundaries
and resulted in the creation of new
independent states, including Poland,
Finland, the Baltic states,
Czechoslovakia, and Yugoslavia. The
League of Nations was established to
maintain world peace, but its failure to
manage instability during the interwar
period contributed to the outbreak of
World War II in 1939.

Names

Before World War II, the events of

1914–1918 were generally known as
the Great War or simply the World
War.[1] In August 1914, the magazine
The Independent wrote "This is the
Great War. It names itself."[2] In
October 1914, the Canadian magazine
Maclean's similarly wrote, "Some wars
name themselves. This is the Great
War."[3] Contemporary Europeans also
referred to it as "the war to end war"
and it was also described as "the war
to end all wars" due to their perception
of its unparalleled scale, devastation,
and loss of life.[4] The first recorded
use of the term First World War was in
September 1914 by German biologist
and philosopher Ernst Haeckel who
stated, "There is no doubt that the
course and character of the feared
'European War' ... will become the first
world war in the full sense of the
word."[5]

Background

Main article: Causes of World War I

Political and military alliances

Rival military coalitions in 1914:[c]

Triple Entente
Triple Alliance

For much of the 19th century, the

major European powers maintained a
tenuous balance of power, known as
the Concert of Europe.[6] After 1848,
this was challenged by Britain's
withdrawal into so-called splendid
isolation, the decline of the Ottoman
Empire, New Imperialism, and the rise
of Prussia under Otto von Bismarck.
Victory in the 1870–1871 Franco-
Prussian War allowed Bismarck to
consolidate a German Empire. Post-
1871, the primary aim of French policy
was to avenge this defeat,[7] but by
the early 1890s, this had switched to
the expansion of the French colonial
empire.[8]

In 1873, Bismarck negotiated the

League of the Three Emperors, which
included Austria-Hungary, Russia, and
Germany. After the 1877–1878 Russo-
Turkish War, the League was dissolved
due to Austrian concerns over the
expansion of Russian influence in the
Balkans, an area they considered to be
of vital strategic interest. Germany and
Austria-Hungary then formed the 1879
Dual Alliance, which became the Triple
Alliance when Italy joined in 1882.[9]
For Bismarck, the purpose of these
agreements was to isolate France by
ensuring the three empires resolved
any disputes among themselves. In
1887, Bismarck set up the Reinsurance
Treaty, a secret agreement between
Germany and Russia to remain neutral
if either were attacked by France or
Austria-Hungary.[10]

World empires and colonies c. 1914

For Bismarck, peace with Russia was

the foundation of German foreign
policy, but in 1890, he was forced to
retire by Wilhelm II. The latter was
persuaded not to renew the
Reinsurance Treaty by his new
Chancellor, Leo von Caprivi.[11] This
gave France an opening to agree to the
Franco-Russian Alliance in 1894,
which was then followed by the 1904
Entente Cordiale with Britain. The
Triple Entente was completed by the
1907 Anglo-Russian Convention. While
not formal alliances, by settling
longstanding colonial disputes in Asia
and Africa, British support for France
or Russia in any future conflict became
a possibility.[12] This was accentuated
by British and Russian support for
France against Germany during the
1911 Agadir Crisis.[13]

Arms race

SMS Rheinland, a Nassau-class

battleship, Germany's first
response to the British
Dreadnought, 1910

German economic and industrial

strength continued to expand rapidly
post-1871. Backed by Wilhelm II,
Admiral Alfred von Tirpitz sought to
use this growth to build an Imperial
German Navy, that could compete with
the British Royal Navy.[14] This policy
was based on the work of US naval
author Alfred Thayer Mahan, who
argued that possession of a blue-
water navy was vital for global power
projection; Tirpitz had his books
translated into German, while Wilhelm
made them required reading for his
advisors and senior military personnel.
[15]

However, it was also an emotional

decision, driven by Wilhelm's
simultaneous admiration for the Royal
Navy and desire to surpass it.
Bismarck thought that the British
would not interfere in Europe, as long
as its maritime supremacy remained
secure, but his dismissal in 1890 led to
a change in policy and an Anglo-
German naval arms race began.[16]
Despite the vast sums spent by Tirpitz,
the launch of HMS Dreadnought in
1906 gave the British a technological
advantage.[14] Ultimately, the race
diverted huge resources into creating
a German navy large enough to
antagonise Britain, but not defeat it; in
1911, Chancellor Theobald von
Bethmann Hollweg acknowledged
defeat, leading to the Rüstungswende
or 'armaments turning point', when he
switched expenditure from the navy to
the army.[17]

This decision was not driven by a

reduction in political tensions but by
German concern over Russia's quick
recovery from its defeat in the Russo-
Japanese War and the subsequent
1905 Russian Revolution. Economic
reforms led to a significant post-1908
expansion of railways and
transportation infrastructure,
particularly in its western border
regions.[18] Since Germany and
Austria-Hungary relied on faster
mobilisation to compensate for their
numerical inferiority compared to
Russia, the threat posed by the closing
of this gap was more important than
competing with the Royal Navy. After
Germany expanded its standing army
by 170,000 troops in 1913, France
extended compulsory military service
from two to three years; similar
measures were taken by the Balkan
powers and Italy, which led to
increased expenditure by the
Ottomans and Austria-Hungary.
Absolute figures are difficult to
calculate due to differences in
categorising expenditure since they
often omit civilian infrastructure
projects like railways which had
logistical importance and military use.
It is known, however, that from 1908 to
1913, military spending by the six
major European powers increased by
over 50% in real terms.[19]

Conflicts in the Balkans

Ethno-linguistic map of Austria-Hungary,

1910. Bosnia-Herzegovina was annexed in
1908.

Sarajevo citizens reading a poster

with the proclamation of the
Austrian annexation in 1908

The years before 1914 were marked by

a series of crises in the Balkans, as
other powers sought to benefit from
the Ottoman decline. While Pan-Slavic
and Orthodox Russia considered itself
the protector of Serbia and other Slav
states, they preferred the strategically
vital Bosporus straits to be controlled
by a weak Ottoman government,
rather than an ambitious Slav power
like Bulgaria. Russia had ambitions in
northeastern Anatolia while its clients
had overlapping claims in the Balkans.
These competing interests divided
Russian policy-makers and added to
regional instability.[20]

Austrian statesmen viewed the

Balkans as essential for the continued
existence of their Empire and saw
Serbian expansion as a direct threat.
The 1908–1909 Bosnian Crisis began
when Austria annexed the former
Ottoman territory of Bosnia and
Herzegovina, which it had occupied
since 1878. Timed to coincide with the
Bulgarian Declaration of Independence
from the Ottoman Empire, this
unilateral action was denounced by
the European powers, but accepted as
there was no consensus on how to
resolve the situation. Some historians
see this as a significant escalation,
ending any chance of Austria
cooperating with Russia in the
Balkans, while also damaging
diplomatic relations between Serbia
and Italy.[21]

Tensions increased after the 1911–

1912 Italo-Turkish War demonstrated
Ottoman weakness and led to the
formation of the Balkan League, an
alliance of Serbia, Bulgaria,
Montenegro, and Greece.[22] The
League quickly overran most of the
Ottomans' territory in the Balkans
during the 1912–1913 First Balkan War,
much to the surprise of outside
[23]