The basic part of the collection contains political correspondence of Polish Christian Labor Party - Stronnictwo Pracy and its leader Karol Popiel with the European Federal Movement and the Christian Democratic Union of the Central Union. There are records on Polish-Czech cooperation in federalism, thw activities of the Council of National Unity - Rada Jednosci Narodowej (1944-1945) and the Polish National Democratic Committee - Polski Narodowy Komitet Demokratyczny in London and Washington. There are underground publications and unpublished typescripts on the activities of UNIA, the ideological branch of the SP in Poland (1940-1945). The political materials of Stronnictwo Pracy include minutes, resolutions, and reports of General Meeting in Belgium (1948), Paris (1956) and in Rome (1978), materials of Ruch Chrzescijansko Spoleczny - Polish Christian Social Movement (RCS). In the series are also articles and publications on Christian Democratic issues (eg. "General Sikorski w mojej pamieci" by Karol Popiel). There are also bulletins published by the Christian Democratic Union of Central Europe in New York (CHRISTIAN DEMOCRATIC REVUE, 1954-1961) and published by the Polish Christian Labor Party (NOUVEL HORIZON - 1957-1959; R.C.S - 1947-1948; DROGA - ROAD -1947; REFORMA-REFORM -1947-1948; ODNOWA -RENEWAL - 1952-1961;1981-1984). The series - Archive of Polish Christian Labor Party, London Branch contains correspondence, lists of members, minutes, resolutions, and reports on the activities of SP-PCLP in England. The series - Zbigniew Ossowski Papers contains his political correspondence (1950-1974), speeches, articles and lectures (1950-1983). There is also political Diary by Zbigniew Ossowski (1944-1952). The series - Konrad Sieniewicz Papers contains his political correspondence as the Secretary General of the Polish Christian Labor Party (PCLP) in France (1950-1955). There is also report on the Warsaw Uprising 1944 by Konrad Sieniewicz, who was in this time an Administrative Delegate of the Underground Government for District No. 1 in Warsaw. To the series was included reports of the Assembly of Captive European Nations (1955-1956). The series - Kazimierz Studentowicz Papers contains underground publications and unpublished typescripts documenting the activities of Unia, the ideological branch of the Stronnictwo Pracy and an agreement between UNIA and Stronnictwo Pracy (1941-1942). There are also publications of Kazimierz Studentowicz on important political and economical issues in Poland after World War II (1941-1981). Arrangement in Series: Archive of the Polish Christian Labor Party, Archive of the Polish Christian Labor Party - London Branch, Konrad Sieniewicz Papers, Zbigniew Ossowski Papers, Kazimierz Studentowicz Papers, Janusz Sleszynski Papers.

The collection contains records of Polish Christian Labor Party (Stronnictwo Pracy) and is named Karol Popiel Papers to commemorate its leader. Karol Popiel (1887-1977) was the founder and chairman of Stronnictwo Pracy (Labor Party - SP) and former Minister of the Polish Government-in-Exile in London.He was the Leader of the Polish Christian Democratic Movement in exile. Acquisition Note: This collection was completed by members of the SP (1976-2000). Gift of Karol Popiel, Konrad Sieniewicz - General Secretary of the SP, Zbigniew Ossowski and Zofia Fedorowicz - Grzelak. W 2015 doinwentaryzowanie 72 jednostek (1mb.) Dar z 2012 roku od Zofii Grzelak.