The Ukrainian forces withdrew outside Lwów 's confines by 21 November 1918 , after which elements of Polish soldiers began to loot and burn much of the Jewish and Ukrainian quarters of the city , killing approximately 340 civilians ( see : Lwów pogrom ) . The retreating Ukrainian forces besieged the city . The Sich riflemen reformed into the Ukrainian Galician Army ( UHA ) . The Polish forces aided from central Poland , including General Haller 's '' Blue Army '' , equipped by the French , relieved the besieged city in May 1919 forcing the UHA to the east
Lwów pogrom
Lwów pogrom (1918)
Lviv