This article needs attention from an expert on the subject. (May 2018)
|Part of World War I|
Clockwise from top left: soldiers stationed in the Carpathian Mountains, 1915; German soldiers in Kiev, March 1918; the Russian ship Slava, October 1917; Russian infantry, 1914; Romanian infantry
| German Empire|
Ottoman Empire (1916–17)
| Russian Empire (1914–17)|
Russian Republic (1917)
British Empire (1916–17)
Soviet Russia (1918)
|Commanders and leaders|
|Casualties and losses|
- 173,858 killed
- 1,151,153 wounded
- 143,818 captured
- 730,000 dead
- 2,172,000 wounded
- 1,479,000 missing or captured
- 10,000 captured
- 3,749,000 wounded
- 3,343,900 captured[nb 1]
|Civilian deaths: |
410,000 died due to military action
730,000 died of war-related causes
Kingdom of Romania:
130,000 died due to military action
200,000 died of war-related causes
120,000 civilians died due to military action
467,000 civilians died of war-related causes
The Eastern Front or Eastern Theater of World War I (German: Ostfront, Russian: Восточный фронт, Vostochnıy 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. Meanwhile, a revolution occurred in Russia in February 1917 (one of the several causes being the hardships of the war). Tsar Nicholas II was forced to abdicate and a Russian Provisional Government was founded, with Georgy Lvov as its first leader, who was eventually replaced by Alexander Kerensky.
The newly formed Russian Republic continued to fight the war alongside Romania and the rest of the Entente until it was overthrown by the Bolsheviks in October 1917. Kerensky oversaw the July Offensive, which was largely a failure and caused a collapse in the Russian Army. The new government established by the Bolsheviks signed the Treaty of Brest-Litovsk with the Central Powers, taking it out of the war and making large territorial concessions. Romania was also forced to surrender and signed a similar treaty, though both of the treaties were nullified with the surrender of the Central Powers in November 1918.
The front in the east was much longer than that in the west. The theater of war was roughly delimited by the Baltic Sea in the west and Minsk in the east, and Saint Petersburg in the north and the Black Sea in the south, a distance of more than 1,600 kilometres (990 mi). This had a drastic effect on the nature of the warfare.
While World War I on the Western Front developed into trench warfare, the battle lines on the Eastern Front were much more fluid and trenches never truly developed. This was because the greater length of the front ensured that the density of soldiers in the line was lower so the line was easier to break. Once broken, the sparse communication networks made it difficult for the defender to rush reinforcements to the rupture in the line, mounting rapid counteroffensives to seal off any breakthrough.