In May 1926 Józef Piłsudski took power in Poland through a Coup D'état. Piłsudski's reign marked the much-needed improvement in the situation of ethnic minorities. Piłsudski replaced the National-Democratic "ethnic assimilation" with a "state assimilation" policy: citizens were judged by their loyalty to the state, not by their nationality. In 1930 the Ukrainian Scientific Institute was established with government funding. Until the outbreak of the Second World War, the institute managed to publish more books than any other interwar émigré or Western Ukrainian academic publisher, including the works of Taras Shevchenko in 13 volumes (16 planned) and the series of major liturgical texts in Ukrainian translation. The Institute conducted in-depth scientific research into Ukrainian cultural history. However the continuing series of terrorist attacks by the Organization of Ukrainian Nationalists to sabotage Piłsudski's efforts, resulted in government pacifications and meant that the situation continued to degenerate, despite Piłsudski's efforts.