He graduated in history from Warsaw University in 1937.
Director of Research into origins of Polish State 1949-1953, Pro-Rector 1956-1959, Director Historical Institute 1955-1975. President University Commission, of State Education Council 1960-1969. President 1975-1980, President 1980-1985).
Association Professor College, de France 1968.
Correspondent Fellow, Medieval Academy, of America since 1968. Association Royal Historical Society since 1981.
Visiting Fellow, All Souls College, Oxford 1968-1969. Visiting Professor, Harvard University 1977-1978.
Chairman Scientific Council of Historical Institute, Polish Academy, of Sciences 1972-1980, National Committee International Council of Museums since 1981.
Chairman Scientific Council of National Library 1972-1977. Director Royal Castle Warsaw since 1980. President 1980-1983, since 1990), Warsaw Learned Society since 1952 (President since 1986), Koninklijke Akademie voor Wetenschappen, Brussels 1972, Academy Royale de Belgique 1976, Academy National des Sciences, BellesLettres et Arts de Bordeaux, Academy Belles Lettres 1981.
Royal Swedish Academy 1982, British Academy 1985.
Participant Round Table plenary debates February-April 1989. Honorary degree (Aix-Marseille, Bordeaux, Paris IV-Sorbonne, Budapest, Moscow, Oxford and Poznan Universities).
State. Commander Crosses of.
Bureau Institute Committee of Historical Sciences since 1965. Comity Institute de Paleographic. Polish Academy, of Sciences since 1972.
Married Irena Czamecka in 1938.