
“Military coalition in World War I The Central Powers, also known as the Central Empires, were one of the two main coalitions that fought in World War I (1914–1918). It consisted of the German Empire, Austria-Hungary, the Ottoman Empire, and the Kingdom of Bulgaria; this was also known as the Quadruple Alliance.”
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Treaty of Brest-Litovsk
1917–1918
The treaty facilitated Russia's exit from World War I, altering the course of the conflict and the map of Eastern Europe.