In its present form, the PTS has had a continuous existence since 1956, but its history can be traced back to 1927, when Florian Znaniecki established the first Polish organization of sociologists under the name of "Polish Sociological Institute" "(Polski Instytut Socjologiczny/PIS)". Initially, the PIS combined the tasks of a research institute with the representation of sociologists across the country. In 1931, on the first ever national convention of sociologists in Poznań, separate professional organization under the name of "Polskie Towarzystwo Socjologiczne (PTS)" was created on Znaniecki's initiative. This association, one of the first of its type in Europe, co-existed with the PIS. Relatively little is known about its activities. Its first two presidents were Ludwik Krzywicki (1931-1935) and Stefan Czarnowski (1935-1938). In 1935, PTS and PIS jointly organized the second Polish Sociologocial Convention in Warsaw. Both bodies existed until the outbreak of World War II in 1939. Towards the end of the war, in 1944 the PIS was reactivated in the Soviet-controlled part of the country, but not so the PTS; some of its previous tasks were reassigned to the new PIS.