The western part of modern Belarus remained part of the Second Polish Republic. After an early period of liberalization, tensions between increasingly nationalistic Polish government and various increasingly separatist ethnic minorities started to grow, and the Belarusian minority was no exception.  The polonization drive was inspired and influenced by the Polish National Democracy, led by Roman Dmowski, who advocated refusing Belarusians and Ukrainians the right for a free national development. A Belarusian organization, the ''Belarusian Peasants' and Workers' Union'', was banned in 1927, and opposition to Polish government was met with state repressions. Nonetheless, compared to the (larger) Ukrainian minority, Belarusians were much less politically aware and active, and thus suffered fewer repressions than the Ukrainians. In 1935, after the death of Józef Piłsudski, a new wave of repressions was released upon the minorities, with many Orthodox churches and Belarusian schools being closed. Use of the Belarusian language was discouraged. Belarusian leadership was sent to Bereza Kartuska prison.