1918
World War 1 and World War 2 And we cannot leave out the Cold War
Russia :)
Russia as they were dealing with the Bolshevik Revolution
in 1917 russia withdrew from the war specifically December 1917
1917.
Russia last full year of World War I
Russia
22 Jun 1941 when Germany invaded Russia
The Revolution in Russia ended Russia's involvement
Russia joined world war 1 in 1914
Czar Nicholas II controlled Russia during World War I. He lost power during the final year Russia was in the war and the Alexander Kerensky was in power for the final months before Lenin took over and negoitated Russia's surrender to Germany.