Answer:
In March 1918, in return for Russia's peaceful withdrawal from the war, the Treaty of Brest-Litovsk obligated Russia to hand over roughly one third of the Russian Empire´s population, territory and resources to Germany.
Explanation:
In March 1918, Russia ceased its participation in WWI by signing a treaty in the city of Brest-Litovsk. This was a treaty between them and the Central Powers (conformed by Germany, the Ottoman Empire, Bulgaria and Austria-Hungary), in which Russia had to hand over territory to Germany. However, by November 11, 1918, the treaty was revoked thanks to the armistice, and one year later, after the signing of the Treaty of Versailles, Germany had to give back this territory because of their losing the war.
