The Germans responded by repudiating the ceasefire, seized much of the Ukraine, Belarus, and the Baltic States before threatening the Russian capital, Petrograd. The Russians had little choice but to return to the negotiating table. On 3rd March 1918 the representatives of the belligerents signed a treaty at Brest-Litovsk in modern day Belarus.
The terms of the treaty were even more unfavourable to the Russians than those they had previously rejected. The fourteen articles of the treaty included provisions for the Central Powers to take effective control of the Baltic states, Finland, Belarus and the Ukraine. The Russians were also to return those lands captured from the Ottoman Empire. In return the Ottoman’s accepted the creation of the Democratic Republic of Armenia.
The treaty did not last long: the Ottomans invaded Armenia just two months after the signing of the treaty; then the Germans renounced it in November 1918 as a response to Bolshevik attempts to provoke revolution in Germany. Russia itself annulled the treaty after the Allied victory over Germany and her allies. Over the next three years the Soviet Union reclaimed some of its lost territory in a series of military campaigns.
The text of The Peace Treaty of Brest-Litovsk is available on the World War I Document Archive site.