Editing First World War (section)

== Course of the war ==

=== Western Front ===

German forces advanced through Belgium and northern France in August 1914. The advance was stopped at the [[First Battle of the Marne]] from 6 to 12 September. Both sides then extended their positions northward until a continuous front ran from the Swiss border to the North Sea. Trenches and artillery positions became the main features of the front.

The Western Front remained largely fixed from late 1914 until 1918. Allied and German armies attempted to break the defensive system through prolonged offensives. The [[Battle of Verdun]] began in February 1916 and continued until December. The [[Battle of the Somme]] began on 1 July 1916 and lasted into November. Both battles caused very high losses without producing a decisive strategic breakthrough.

France launched the Nivelle Offensive in April 1917. Its failure contributed to mutinies in parts of the French Army, although French forces continued to hold the front. British and Commonwealth troops fought the Third Battle of Ypres later that year. Heavy rain and damaged drainage turned much of the battlefield into mud.

=== Eastern and Balkan fronts ===

The Eastern Front covered a far larger area than the Western Front and remained more mobile. Germany defeated a Russian army at the [[Battle of Tannenberg]] in August 1914. Russian forces fought Austria-Hungary in Galicia and later withdrew from Poland during the Central Powers' offensive of 1915.

Serbia resisted Austro-Hungarian invasions in 1914. A combined German, Austro-Hungarian and Bulgarian offensive overran the country in late 1915. The Serbian army retreated through Albania and was later reorganized on the Salonika Front. Allied forces remained around Thessaloniki until their offensive in September 1918 broke Bulgarian resistance.

Romania entered the war on the Allied side on 27 August 1916. Central Powers forces captured Bucharest in December and occupied much of the country. Romania continued limited resistance from [[Moldavia]] before signing an armistice in December 1917. It re-entered the war on 10 November 1918.

Russia's military position weakened during 1917. The February Revolution removed Nicholas II, while the October Revolution brought the Bolsheviks to power. The new government signed the [[Treaty of Brest-Litovsk]] with the Central Powers on 3 March 1918 and withdrew Russia from the war. The treaty transferred extensive territories in eastern Europe out of Russian control.

=== Italy and the Ottoman Empire ===

Italy declared war on Austria-Hungary on 23 May 1915 after joining the Allies. Most fighting occurred along the Isonzo River and in the Alpine border region. Eleven Italian offensives on the Isonzo failed to produce a decisive result. The Central Powers broke through at [[Battle of Caporetto|Caporetto]] in October 1917, forcing an Italian withdrawal to the Piave River. Italy recovered and defeated Austria-Hungary at [[Battle of Vittorio Veneto|Vittorio Veneto]] in October 1918.

The Ottoman Empire entered the war in late 1914. Allied forces attempted to open the Dardanelles during the [[Gallipoli campaign]] of 1915. The landings failed, and the remaining Allied troops withdrew by January 1916. Ottoman forces fought Russia in the Caucasus and Britain in Mesopotamia.

British-led forces advanced through Sinai and Palestine from 1916. The [[Arab Revolt]] began in June of that year against Ottoman rule in the Hejaz. British forces captured Jerusalem in December 1917 and Damascus in October 1918. The Ottoman government signed the Armistice of Mudros on 30 October 1918.

=== Africa and the Pacific ===

The Allies attacked German colonies after the outbreak of war. Togoland surrendered in August 1914. German South West Africa was occupied in 1915. Fighting in German East Africa continued after the European armistice because forces under [[Paul von Lettow-Vorbeck]] remained in the field.

Belgian forces entered German-ruled Rwanda in 1916. After Germany's defeat, Rwanda and Burundi were administered by Belgium as [[Ruanda-Urundi]].

Japan entered the war against Germany on 23 August 1914. Japanese and British forces captured the German base at Qingdao in November. Japan occupied German island possessions north of the equator. Australia and New Zealand took other German territories in the Pacific.

=== War at sea and United States entry ===

Britain used its naval strength to blockade Germany and restrict imports. The German High Seas Fleet challenged the British Grand Fleet at the [[Battle of Jutland]] from 31 May to 1 June 1916. The battle caused heavy losses but did not end British control of the North Sea.

Germany relied increasingly on submarines to attack shipping bound for Allied ports. The sinking of the passenger ship ''Lusitania'' on 7 May 1915 damaged relations with the [[United States]]. Germany resumed unrestricted submarine warfare on 1 February 1917, allowing U-boats to attack ships without warning in designated waters.

The United States declared war on Germany on 6 April 1917. German submarine policy and the [[Zimmermann Telegram]] influenced the decision. American troops arrived in increasing numbers during 1918 and strengthened the Allied position on the Western Front.

=== Final year ===

Russia's withdrawal allowed Germany to transfer troops west. Germany began the Spring Offensive on 21 March 1918 and advanced across parts of the old Somme battlefield. The offensive failed to separate the British and French armies or force an Allied peace. German losses weakened the army before large American formations had fully entered combat.

The Allies began the [[Hundred Days Offensive]] on 8 August 1918. German forces were pushed back from positions held since 1914. The Central Powers could no longer replace men and equipment at the required rate.

Bulgaria signed the Armistice of Salonica on 29 September. The Ottoman Empire signed the Armistice of Mudros on 30 October. Austria-Hungary signed the Armistice of Villa Giusti on 3 November as its government lost control over its constituent territories.

Political unrest spread through Germany during October and November. Wilhelm II abdicated on 9 November, and a republic was proclaimed in Berlin. The German delegation signed the armistice at Le Francport early on 11 November. It entered into force at 11:00 and ended fighting on the Western Front.