Lviv University (Львівський університет) or officially the Ivan Franko National University of Lviv (Львівський національний університет імені Івана Франка) is the oldest continuously operating university in Ukraine. It is located in the historic city of Lviv in Lviv Oblast of western Ukraine. The university was founded on January 20, 1661 when King John II Casimir of Poland issued the diploma granting the city's Jesuit Collegium, founded in 1608, "the honour of the academy and the title of the university".
The Jesuits had tried to create the university earlier, in 1589, but did not succeed. Establishing another college in Poland was seen as a threat by authorities of Kraków 's Jagiellonian University, who did not want a rival and for many years managed to halt plans of the Jesuits. King John II Casimir was a sympathizer of the Jesuits and his stance was crucial. The royal diploma was confirmed by another act issued in Częstochowa on February 5, 1661. Creation of the school was also stipulated by the Treaty of Hadiach. One of its articles stated that a Ruthenian academy was to be created in Kiev and another one should be created in an unspecified location, most likely in Lviv, which was an important center of the Greek Catholic church.
In the period 1939-1941 the Soviets executed over a dozen members of the Polish faculty. In July 1941 the Nazi German occupiers closed the university, followed by the massacring two dozen Polish professors (as well as members of their households and guests, increasing the total number of victims to above forty), who included members of other academic institutions, too. The extent to which Ukrainian nationalists may have been involved in identifying and selecting some of the victims is still a matter of debate, as Polish historian Adam Redzik wrote, while the Ukrainian nationalist students helped prepare lists of Polish intellectuals, it is unlikely they expected or knew about their intended purposes (i.e. the executions). In the summer of 1944, the advancing Red Army, assisted by Polish Home Army forces locally implementing Operation Burza, pushed the Wehrmacht out of Lviv and the university reopened. At first, its academic staff consisted of Poles, but within the following months most of them, together with the Polish population of the city, were "evacuated" in the expelled, as Stalin had moved Poland's borders far to the west. The traditions of Jan Kazimierz University have been preserved at the University of Wrocław, which was established after the German inhabitants of that city had been expelled following Stalin's establishing Germany's eastern border farther to the west.