To whom did the Russians surrender in late 1917 during WWI?

In late 1917, the Russians surrendered to Germany as a result of the Treaty of Brest-Litovsk, which was signed in March 1918. This treaty ended Russia's involvement in World War I following the Bolshevik Revolution in October 1917. The new Bolshevik government sought to withdraw from the war in order to focus on internal issues and consolidate their new power. The surrender was significant as it allowed Germany to concentrate its military efforts on the Western Front without the distraction of fighting on the Eastern Front. The terms of the treaty were harsh for Russia, resulting in significant territorial losses and impact on Russia's national interests.