Professor Jerzy Tomaszewski was a historian and political scientist, staff member and lecturer at the Institute of History of the University of Warsaw. In 1954, he received a Master’s degree in economic history at the Main School of Planning and Statistics. Gradually, he became a doctor (1960), habilitated doctor(1964), associate professor (1972) and full professor (1980). He worked at the Department of Economic History of the Main School of Planning and Statistics; in the years 1965–1970 he was a docent and head of the Institute of Political Sciences of Warsaw University of Life Sciences, and from 1970 he worked also at the Institute of Political Sciences at the University of Warsaw. Since 1990 he was the Head of the Mordechaj Anielewicz Center for the Study and Teaching of the History and Culture of Jews in Poland and a research worker of the Institute of History of the University of Warsaw. He retired in 2002, still giving lectures at the Institute of History. Working at the University of Warsaw, he promoted and reviewed doctoral and habilitation theses of the most eminent historians and researchers in the field of the history and culture of Polish Jews, inter alia: Marcin Urynowicz: Adam Czerniaków 1880–1942. Życie i Działalność. (Adam Czerniaków 1880–1942. Life and Activity); August Grabski: Działalność komunistów wśród Żydów w Polsce (1944–1949) (The Activity of Communists Among Jews in Poland (1944–1949); Natalia Aleksiun-Mędrzak: Ruch syjonistyczny w Polsce 1944–1950 (The Zionist Movement in Poland 1944–1950); Artur Markowski: Rodzina Żydów suwalskich w pierwszej połowie XIX wieku (The Family of Jews from Suwałki in the First Half of the 19th Century); Michał Galas: Rabin Markus Jastrow i jego wizja reformy judaizmu. Studium z dziejów judaizmu w XIX wieku (Rabbi Markus Jastrow and His Vision of the Reform of Judaism. A Case Study from the History of Judaism in the 19th Century); Joanny Nalewajko-Kulikov: Od chederu do partii. Biografia żydowskiego komunisty na przykładzie Dawida Sfarda (1905–1981) (From Cheder to Party. Biography of a Jewish Communist on the Example of Dawid Sward(1905–1981)); Anna Landau-Czajka: W jednym stali domu. Koncepcje rozwiązania kwestii żydowskiej w publicystyce polskiej lat 1933–1939 (In One House They Stood. Concepts of the Solution to the Jewish Question in Polish Journalism of 1933–1939); Jolanta Żyndul: Autonomia narodowo-kulturalna jako propozycja rozwiązania problemów etnicznych w Europie Środkowo-Wschodniej. Izaak Grünbaum oraz inni eksponenci koncepcji (1898–1998) (The National-Cultural Autonomy as a Proposal for Solving Ethnical Problems in East-Central Europe); Dariusz Libionka: ”Kwestia żydowska” w prasie katolickiej w Polsce w latach trzydziestych XX wieku (”Jewish Question” in the Catholic Press in Poland in the 1930s).
The Professor also worked at the Jewish Historical Institute — he was a member of the Academic Council (1970) and the Board (1985). He was also part of the editorial committee of the JHI Bulletin and a member of the committee awarding the Jan Karski and Pola Nireńska Prize (he himself was a laureate of this prize in 1999).
Professor Jerzy Tomaszewski was the author of around a thousand publications, inter alia, concerning the history of national minorities and the history of Jews: Z dziejów Polesia 19211939 (1963) (From the History of Polesie; Sprawa żyrardowska(The Żyrardów Case)(co-author Zbigniew Landau, 1983); Rzeczpospolita wielu narodów (1985)(Rzeczpospolita of Many Nations); Zarys dziejów Żydów w Polsce w latach 1918–1939 (1990) (The Outline of the History of Jews in Poland in the Years 1918–1939); Mniejszości narodowe w Polsce XX wieku (1991) (National Minorities in Poland in the 20th Century); Preludium Zagłady. Wygnanie Żydów polskich z Niemiec w 1938 r. (1998) (A Prelude to the Holocaust. The Exile of Polish Jews from Germany in 1938); Izrael (Israel)(co-author Andrzej Chojnowski, 2005).