In Soviet Russia, the Bolsheviks, whose revolution had succeeded partly on their promises to a war-weary citizenry and military to disengage from World War I, declared its pacifist intentions to the Central Powers. A ceasefire agreement was signed on December 15, 1917 and peace talks began a few days later in Brest-Litovsk (present-day Brest, in Belarus).
However, the Central Powers imposed territorial demands that the Russian government deemed excessive. On February 17, 1918, the Central Powers repudiated the ceasefire agreement, and the following day, Germany and Austria-Hungary restarted hostilities against Russia, launching a massive offensive with one million troops in 53 divisions along three fronts that swept through western Russia and captured Ukraine Belarus, Lithuania, Latvia, and Estonia. German forces also entered Finland, aiding the non-socialist paramilitary group known as the “White Guards” in defeating the socialist militia known as “Red Guards” in the Finnish Civil War. Eleven days into the offensive, the northern front of the German advance was some 85 miles from the Russian capital of Petrograd (on March 12, 1918, the Russian government transferred its capital to Moscow).
On February 23, 1918, or five days into the offensive, peace talks were restarted at Brest-Litovsk, with the Central Powers demanding from Russia even greater territorial and military concessions than in the December 1917 negotiations. After heated debates among members of the Council of People’s Commissars (the highest Russian governmental body) who were undecided whether to continue or end the war, at the urging of its Chairman, Vladimir Lenin, the Russian government acquiesced to the Treaty of Brest-Litovsk. On March 3, 1918, Russian and Central Powers representatives signed the treaty, whose major stipulations included the following: peace was restored between Russia and the Central Powers comprising Germany, Austria-Hungary, Bulgaria, and the Ottoman Empire; Russia relinquished possession of Finland (which was currently embroiled in a civil war), Belarus, Ukraine, and the Baltic territories of Estonia, Latvia, and Lithuania – Germany and Austria-Hungary were to determine the future of these territories; and Russia also ceded to the Ottoman Empire the regions of Ardahan, Kars, and Batumi in the Caucasus.
Subsequently, German forces occupied Estonia, Latvia, Lithuania, Belarus, Ukraine, and Poland, establishing semi-autonomous governments in these territories that were subordinate to the authority of the German monarch, Kaiser Wilhelm II. The German occupation of the region allowed the realization of the Germanic vision of “Mitteleuropa”, an expansionist ambition aimed at unifying all Germanic and non-Germanic peoples of Central Europe into a greatly enlarged and powerful German Empire. In support of Mitteleuropa, in the Baltic region, the Baltic German nobility proposed to set up the United Baltic Duchy, a semi-autonomous political entity consisting of present-day Latvia and Estonia that would be voluntarily integrated into the German Empire. The proposal was not implemented, but German military authorities set up local civil governments under the authority of the Baltic German nobility or ethnic Germans.
Although the Treaty of Brest-Litovsk in March 1918 ended Russia’s participation in World War I, the war was still ongoing in other fronts – most notably on the Western Front, where for four years, German forces were bogged down in inconclusive warfare against the British, French and other Allied Armies. After transferring substantial numbers of now freed troops from the Russian front to the Western Front, in March 1918, Germany launched the Spring Offensive, a major attack into France and Belgium in an effort to bring the war to an end. After four months of fighting, by July 1918, despite achieving some territorial gains, the German offensive had ground to a halt.
The Allied Powers then counterattacked with newly developed battle tactics and weapons and gradually pushed back the now spent and demoralized German Army all across the line into German territory. The entry of the United States into the war on the Allied side was decisive, as increasing numbers of arriving American troops with the backing of the U.S. weapons-producing industrial power contrasted sharply with the greatly depleted war resources of both the Entente and Central Powers. The imminent collapse of the German Army was greatly exacerbated by the outbreak of political and social unrest at the home front (the German Revolution of 1918-1919), leading to the sudden end of the German monarchy with the abdication of Kaiser Wilhelm II on November 9, 1918 and the establishment of an interim government (under moderate socialist Friedrich Ebert), which quickly signed an armistice with the Allied Powers on November 11, 1918 that ended the combat phase of World War I.
As the armistice agreement required that Germany demobilize the bulk of its armed forces as well as withdraw the same to the confines of the German borders within 30 days, the German government ordered its forces to abandon the occupied territories that had been won in the Eastern Front. After Germany’s capitulation, Russia repudiated the Treaty of Brest-Litovsk and made plans to seize back the European territories it previously had lost to the Central Powers. An even far more reaching objective was for the Bolshevik government to spread the communist revolution to Europe, first by linking up with German communists who were at the forefront of the unrest that currently was gripping Germany. Russian military planners intended the offensive to merely follow in the heels of the German withdrawal from Eastern Europe (i.e. to not directly engage the Germans in combat) and then seize as much territory before the various local ethnic nationalist groups in these territories could establish a civilian government.