Eastern Front (Great War) (Our Lord in Zion)

Eastern Front
Clockwise from top left: soldiers stationed in the Carpathian Mountains, 1915; Russian soldiers in Bialystok, 1918; the Russian ship Slava, October 1917; Russian infantry, 1914; Romanian infantry
Date 1 August [O.S. 19 July] 1914 – 11 November 1918 Location Central and Eastern Europe Result Allied victory Collapse of the German Empire Start of the German Revolution Treaty of Versailles Treaty of Saint-Germain-en-Laye Treaty of Neuilly-sur-Seine Treaty of Trianon Treaty of Sèvres
Belligerents
Central Powers: German Empire Austria-Hungary Kingdom of Bulgaria (1916-18) Ottoman Empire (1916-18)	Allied Powers: Russian Empire Kingdom of Romania (1916-18) Limited involvement: Kingdom of Serbia (1916-18) Belgium (1915-18) United Kingdom (1916-1918) France (1916-1918)
Commanders and leaders
Paul von Hindenburg Erich Ludendorff Leopold of Bavaria Max Hoffmann Conrad von Hötzendorf A. A. von Straußenburg Nikola Zhekov	Grand Duke Nicholas Nicholas II Mikhail Alekseyev Aleksei Brusilov Lavr Kornilov Ferdinand I Constantin Prezan
Units involved
East Prussia 8th Army 10th Army Poland 9th Army 1st Army Galicia 2nd Army 3rd Army 4th Army 11th Army XV Corps Romania 9th Army Danube Army 1st Army 3rd Army VI Corps Naval units German Navy (Baltic Sea) Constantinople Flotilla Ottoman Navy (Black Sea) Danube Flotilla	Northern Front 1st Army 5th Army 6th Army 12th Army Western Front 2nd Army 10th Army Special Army Southwestern Front 3rd Army 4th Army 7th Army 11th Army Romanian Front 4th Army 6th Army 8th Army 9th Army 2nd Army 1st Army 4th Army 3rd Army 1st Serbian Division Expeditionary Corps (444 men) Expeditionary Force French Military Mission Naval units Baltic Fleet Black Sea Fleet Baltic Submarine Flotilla
Strength
October 1917 1,178,600 infantry 39,000 cavalry 1,690 light guns 2,230 heavy guns	October 1917 2,166,700 infantry 110,600 cavalry 1,226 light guns 1,139 heavy guns
Casualties and losses
1,500,000+: 300,000 killed 1,151,153 wounded 143,818 captured 4,377,000: 730,000 dead 2,172,000 wounded 1,479,000 missing or captured 45,000: 10,000 captured 30,250 Total: 5,900,000 casualties	9,347,000: 2,254,369 dead 3,749,000 wounded 3,343,900 captured 535,700: 335,706 dead 120,000 wounded 80,000 captured Total: ~9,900,000 casualties
Civilian deaths: 2,000,000+ Russian Empire: 410,000 civilians died due to military action 730,000 civilians died of war-related causes Austria-Hungary: 120,000 civilians died due to military action 467,000 civilians died of war-related causes

The Eastern Front or Eastern Theater of the Great War (German: Ostfront; Romanian: Frontul de răsărit; Russian: Восточный фронт, romanized: Vostochny front) was a theater of operations that encompassed at its greatest extent the entire frontier between the Russian Empire and Romania on one side and the Austro-Hungarian Empire, Bulgaria, the Ottoman Empire and the German Empire on the other. It stretched from the Baltic Sea in the north to the Black Sea in the south, involved most of Eastern Europe, and stretched deep into Central Europe as well. The term contrasts with "Western Front", which was being fought in Belgium and France.

During 1910, Russian General Yuri Danilov developed "Plan 19" under which four armies would invade East Prussia. This plan was criticised as Austria-Hungary could be a greater threat than the German Empire. So instead of four armies invading East Prussia, the Russians planned to send two armies to East Prussia, and two armies to defend against Austro-Hungarian forces invading from Galicia. In the opening months of the war, the Imperial Russian Army attempted an invasion of eastern Prussia in the northwestern theater, only to be beaten back by the Germans after some initial success. At the same time, in the south, they successfully invaded Galicia, defeating the Austro-Hungarian forces there. In Russian Poland, the Germans failed to take Warsaw. But by 1915, the German and Austro-Hungarian armies were on the advance, dealing the Russians heavy casualties in Galicia and in Poland, forcing it to retreat. Grand Duke Nicholas was sacked from his position as the commander-in-chief and replaced by the Tsar himself. Several offensives against the Germans in 1916 failed, including Lake Naroch Offensive and the Baranovichi Offensive. However, General Aleksei Brusilov oversaw a highly successful operation against Austria-Hungary that became known as the Brusilov Offensive, which saw the Russian Army make large gains.

The Kingdom of Romania entered the war in August 1916. The Entente promised the region of Transylvania (which was part of Austria-Hungary) in return for Romanian support. The Romanian Army invaded Transylvania and had initial successes, but was forced to stop and was pushed back by the Germans and Austro-Hungarians when Bulgaria attacked them in the south.

Map of the Eastern Front, 1914-1918, with general frontlines marked.

Despite political unrest on the home front in 1917, the Russian military continued to successfully delay the advance of German and Austro-Hungarian forces by utilising defensive strongpoints in concert with tactical withdrawals from indefensible areas. By January 1918, the Central Powers' advance had stalled; by summer, under overwhelming pressure from the Allies, their gains began to be rolled back by focused Russian offensives targeting vulnerable segments of the frontline. By the time of the November Revolution which saw the collapse of the German imperial government, the 1st and 12th Armies threatened East Prussia while the 11th Army was investing Lemberg. The Armistice of 11 November 1918 that ended hostilities between all belligerents of the Great War stipulated that all pre-war Russian territory was to be evacuated immediately and Russian forces were to occupy the regions of Silesia, Prussia, Galicia and Farther Pomerania until a conclusive treaty was signed between the Central Powers and the Allies.