Polish–Soviet War in 1919

In 1918, the German Army in the east was the most powerful force in the region. Even more importantly, it was not only undefeated, it was victorious (in contrast to the German Army on the western front). However the commander of the German forces in the east, Max Hoffmann, a chief negotiator in the Treaty of Brest-Litovsk, was facing increasing difficulties. He believed, rightly, that his army was the only stabilising influence over the Eastern Europe. Yet with the disintegration of Austria-Hungary, rise of Bolsheviks in the east and various independent governments between the former frontline and Germany, the former Oberkommando-Ostfront (or Ober-Ost) occupation zone became a thin line to nowhere, connected only to still-German Prussia. The deteriorating situation in Germany, facing the threat of civil war, eventually forced Hoffman to begin to retreat westwards, to Germany, in December 1918. Demoralized officers and mutinous soldiers abandoned their garrisons en masse and returned home. Only a limited number of units still retained any combat strength.

The areas abandoned by the Central Powers became a field of conflict among local governments created by Germany, other local governments that independently sprang up after the German withdrawal, and the Bolsheviks, who hoped to incorporate those areas into Bolshevik Russia. Internal power struggles prevented any of the governments in Belarus from gaining real power. The situation in Ukraine was even more complex, with sizable Ukrainian forces divided and ongoing conflicts among Nestor Makhno's anarchists, the communists, the White Russians, various governments of Ukraine, and the renascent Polish Army. The situation was further complicated when self-defence forces began to form in Lithuania, Estonia and Latvia as well. Many of those groups were fragmented, merged, divided, formed short alliances with others, and almost constantly fought. Almost the entire Eastern Europe was in chaos.

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