Dissipation of Austro-Hungarian republic, which included Galicia, Transcarpathians, and Bukovyna, was the result of the First World War. On November 1st, 1918, West Ukrainian People’s Republic (WUPR) was proclaimed on this territory, which led to the breakout of Ukrainian-Polish war (1918-1919). Having defeated in this conflict, Ukraine gave the majority of WUPR territory together with Volyn to the Republic of Poland.
Up till 1923 territory of the Western Ukraine remained under protectorate of the League of Nations . The government of WUPR, which conducted dyplomatic fight and enjoyed great support from Ukrainians, continued functioning in exile. On March 14th, during the Coucil of the Triple Entante Ambassadors remaining of this territory under the rule of Poland was confirmed by providing Eastern Galicia autonomy. On March 15th, Yevhen Petrushevych’s exile government stopped existing.
But not only the Polish government provided the region with the status of autonomy, but also conducted discriminational and chauvinistic policy concerning the Ukrainians, limiting their national, cultural, and political rights, disseminating everywhere the Polish language and culture. This policy was implemented through creating the so-called “Sokal border” (administrative border between Galicia and north-western Ukrainian lands in order to weaken positions of Ukrainians in Poland), violent treatment of captive UGA soldiers, surpressing any actions against the ruling government.
In spite of the fact that the League of Nations prohibited colonization of trusteeship territory, over the years between the world wars the Polish government resettled on the Ukrainian lands about 300 thousand Polish colonists (the so-called “osadnicy”), who were given 12% of all the land. In response to the Polish occupation of Western-Ukrainian territory, former soldiers of Ukrainian armies created in 1920 the Ukrainian Military Organization (UMO) , which launched struggle against Polish occupational government by conducting fighting, sabotage, and propaganda campaigns.