The main stages of the Ukrainian-Polish war in November 1918 - July 1919, the course of hostilities on the Galician and Volyn-Kholm fronts are considered; analyzed the course of military construction in ZUNR, the process of organizing the Galician Army and the Polish Army, the activities of military-political missions in Eastern Galicia. The influence of the geopolitical situation in Central-Eastern Europe on the course and results of the Ukrainian-Polish armed confrontation in 1919 is shown. For the first time, unpublished documents from the archives of Ukraine, Poland, Russia, and the Czech Republic were involved in scientific circulation.