Marjorie Grace Jacobs AO (26 August 1915 – 12 July 2013) was an Australian historian and emeritus professor at the University of Sydney.

[1] Jacobs lived at Women's College during her undergraduate degree at the University of Sydney and in 1934 won the George Arnold Wood Memorial Prize for first year British history.

[1] Jacobs joined the staff of Sydney University in 1938 as associate lecturer, appointed by Challis Professor of History, Stephen Henry Roberts, for four years.

[5] In 1943–44 she was employed by United States Army's Historical Section in Australia, where she researched medical services in the South-West Pacific.

[7] She was made an Officer of the Order of Australia in the 1988 Queen's Birthday Honours for " service to education, particularly in the field of Indian history".