Polish–Ukrainian conflict (1939–1947)

The Polish–Ukrainian conflict was an ethnic conflict during the Second World War. It would not end until after the war, in 1947. It was fought primarily between irregular Ukrainian and Polish units, with limited participation by Soviet partisans and the Red Army, as well as Romanian, Hungarian, German and Czechoslovak armed formations. Fighting was concentrated in south-eastern Kresy region (today Western Ukraine) of the German-occupied Second Polish Republic.

The occupation of Poland by Germany and Soviet Union in September 1939 led to demands by Ukrainian nationalists for a new Ukrainian state which would include the Polish territories of Eastern Galicia and Wołyń (Volhynia).