The Eastern Front was the theater of war fought in Central and Eastern Europe between Germany, Austria-Hungary, and the Russian Empire.

Unlike the static trench warfare of the Western Front, the Eastern Front was much longer and more fluid.

This led to a war of movement, with large armies maneuvering across vast territories.

The Russian army, though enormous, was poorly equipped, poorly supplied, and often poorly led.

In 1914, Russia launched an invasion of East Prussia but was decisively defeated by the Germans at the Battle of Tannenberg.

The Russians had more success against the Austro-Hungarian army but suffered immense casualties throughout the war.

The brutal conditions and massive losses on the Eastern Front placed enormous strain on the Russian state and society.

This strain was a primary cause of the Russian Revolution in 1917.

Following the Bolshevik seizure of power, Russia signed the Treaty of Brest-Litovsk with Germany in 1918 and exited the war.

The closure of the Eastern Front allowed Germany to transfer its troops to the west for a final offensive.