He was born in Vleuten in the Netherlands to Gerarda and Bartus Jansen, a florist who moved his family to Johnston, Rhode Island in the fall of 1923. Jansen grew up in Massachusetts and graduated from Princeton in 1943, having majored in European history of the Renaissance and Reformation. He served in the Army, studying Japanese and working in the Occupation of Japan. He took his PhD in History at Harvard in 1950, studying Japan with Edwin O. Reischauer and China with John K. Fairbank. His dissertation dealt with the interactions of the two countries and was published as The Japanese and Sun Yat Sen in 1954.
He was a member of the Council on Foreign Relations and of the American Academy of Arts and Sciences and president of the Association for Asian Studies in 1976. In 1999, Jansen was the first foreigner to be honored with the Distinguished Cultural Merit Award, given by the government of Japan.
- The Japanese and Sun Yat-sen (1954)
- Sakamoto Ryōma and the Meiji Restoration (1961)
- Japan and Communist China in the Next Decade (1964)
- Changing Japanese Attitudes Toward Modernization (1965)
- Studies in the institutional history of early modern Japan (1968) John Whitney Hall and Marius Jansen, eds. Princeton, Princeton University Press.
- Japan and its World: Two Centuries of Change (1975)
- Japan and China: from War to Peace, 1894–1972 (1975)
- Japan in Transition, from Tokugawa to Meiji (1986)
- China in the Tokugawa World (1992 ISBN 978-0-674-18476-3) ; DeGruyter 2014) The 1988 Edwin O. Reischauer Lectures
- Japanese Today: Change and Continuity (1995) Edwin O. Reischauer, Marius B. Jansen
- The Making of Modern Japan (2000)
- Library of Congress Authority File: Jansen, Marius B.; retrieved 2011-07-14
- Princeton University, Office of Communications, "Professor Marius Berthus Jansen, scholar of Japanese history, dies," December 13, 2000.
- Marius B. Jansen on the passenger list of the Volendam, September 29, 1923, in New York Passenger Arrival Lists (Ellis Island), 1892–1924
- Saxon, Wolfgang. "Marius B. Jansen, 78, Scholar Of Japanese History and Culture," New York Times. December 26, 2000
- "Obituary: Marius Jansen". Japan Times. 14 December 2000. Retrieved 14 April 2019.
- WorldCat Identities Archived 2010-12-30 at the Wayback Machine: Jansen, Marius B.
- See Chalmers Johnson, "Reviewed Work: Japan and China: From War to Peace, 1894–1972 by Marius B. Jansen" The Journal of Japanese Studies (1975) 2#1 pp. 147–152 online
- Japanese Today Harvard University Press Books
- The Making of Modern Japan Harvard University Press Books
- Ministry of Education, Culture, Sports, Science and Technology (Japan): Culture 2000.