1st Lithuanian–Belarusian Division

The 1st Lithuanian–Belarusian Division (Polish: 1. Dywizja Litewsko-Białoruska, Belarusian: 1-ая Літоўска-Беларуская дывізія, Lithuanian: 1-oji Lietuvos-Baltarusijos divizija) was a volunteer unit of the Polish Army formed around December 1918 and January 1919 during the Polish–Soviet War. It was created out of several dozen smaller units of self-defence forces created out of local volunteers in what is now Lithuania and Belarus amidst a growing series of territory disputes between the Second Polish Republic, the Russian SFSR and several others local provisional governments and took part in several key battles of the war.

With the end of the World War I, a growing series of territorial disputes between Poland, Soviet Russia and several other local provisional governments erupted in a series of wars in Central and Eastern Europe, the most prominent of these being the Polish–Soviet War. Starting in the last years of the First World War, many smaller units of self-defence forces were created out of local volunteers in those areas, among them likely the best known being the Lithuanian and Belarusian Self-Defence ('Samoobrona Litwy i Białorusi'). Self-Defence units were organized in the areas of the Kresy region with Polish majorities or significant minorities – usually urbanized areas like the cities of Vilnius, Minsk, Hrodna, Lida and Kaunas, or towns like Ašmiany, Wilejka, Nemenčinė, Świr and Panevėžys; until December 1918 those units had no central command or organization and many of them were named after the local cities or regions (like 'Samoobrona Lidy'). The first task of those units was curbing the crime wave by German deserters, and later, defence from the pro-Bolshevik groups. Despite its name, most of the members of that organization were either Poles or polonized, and therefore supported the cause of attaching those territories with the newly recreated Polish state.

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