Współpraca wojskowa Polski z Ukraińską Republiką Ludową w okresie wojny z Rosją Radziecką

The aim of this article is to discuss the military cooperation between Poland and the People’s Republic of Ukraine in the period of Polish – Bolshevik war. This cooperation was carried out as a part of joint aspirations to build a security zone guaranteeing for both rising states the possibility of existence in Europe incited by collapsing absolute monarchies. Describing the military cooperation as a derivative of a political agreement, the author refers to many-sided state building aspirations of the Ukrainians. Therefore, the article in an indirect way is also an attempt to approach an internally disintegrated political background of Ukraine, which in extreme cases made impossible or even turned down the eventuality of close relations with the Polish state.