who won?
Polish army
Battle of Radzymin (1920)
The battle was a success for the Poles at both the tactical level (the battle of Radzymin itself) and the strategic level (its role in the battle of Warsaw). 
in which country/region did the battle of radzymin take place? Poland whom was it fought between? Soviet Red Army and Polish Army name a few people from the first group mentioned above who fought in this Ieronim Uborevich and Leon Trotsky and from the second group? General Józef Piłsudski and General Władysław Sikorski on which date did the battle end? August 16, 1920
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Battle of Radzymin (1920) [SEP] Result and assessment
The battle was a success for the Poles at both the tactical level (the battle of Radzymin itself) and the strategic level (its role in the battle of Warsaw). After several days of constant fighting for the town of Radzymin and its immediate vicinity, the Russian attack was repelled and the Poles were able to mount a successful counteroffensive, forcing the Russian armies out of Poland and in the end destroying them completely. However, the conduct of the Polish forces and their commanders at Radzymin in the early part of the battle has been criticized by historians since the 1920s.