The Eastern Front or Eastern Theater of World War I (German: Ostfront, Russian: Восточный фронт, 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.
The use of slaves was reduced, because immigrants could fulfill the same roles as slaves in factories.
