Mina Spiegel Rees was born on August 2, 1902, in Cleveland, Ohio, the youngest of five children of Moses Rees, an insurance agent of German immigrant stock, and Alice Louisa Stackhouse. When Mina was two the family moved to the Bronx, and New York City remained her lifelong base. She attended public schools and then Hunter College High School, an elite school for girls, where she graduated as valedictorian in 1919 after four years of mathematics. She entered Hunter College, then a women’s institution, majored in mathematics, served as class president and editor of the yearbook, and graduated summa cum laude in 1923. While still an undergraduate she began part-time teaching.
After college she taught at Hunter High School while earning a master’s degree in mathematics from Teachers College, Columbia University, in 1925. She briefly sampled law school but returned to mathematics. Hearing that Columbia’s mathematics department was unenthusiastic about women doctoral candidates, she saved money, obtained leave from Hunter, and in 1929 went to the University of Chicago to work with Leonard Eugene Dickson. In 1931 she received her Ph.D. for a dissertation titled “Division algebras associated with an equation whose group has four generators,” published the following year in the American Journal of Mathematics. Dickson, though no longer active in that area, supervised the work. The thesis was soon overtaken by developments associated with Emmy Noether, and Rees did not pursue further research in abstract algebra. She returned to Hunter College as an instructor and rose to associate professor by 1940.
The Second World War redirected her career. In 1943 she joined the Applied Mathematics Panel of the National Defense Research Committee within the Office of Scientific Research and Development, serving as technical aide and executive assistant to its director, Warren Weaver. The panel coordinated university mathematicians on urgent military problems: ballistics, shock waves, fluid dynamics for anti-submarine work, rocketry, and logistics. Rees proved adept at matching problems to talent and at dealing with military officers. She later remarked that she could “sass the admirals as the men couldn’t.” For this service she received the President’s Certificate of Merit and Britain’s King’s Medal for Service in the Cause of Freedom.
After the war the newly created Office of Naval Research invited her to organize its mathematics program. From 1946 she headed the Mathematics Branch, became director of the Mathematical Sciences Division in 1949, and served as deputy science director in 1952–53. In these posts she shaped federal support for basic research at a moment when the United States was deciding how to sustain scientific work in peacetime. She funded not only applied projects but also core mathematics, statistics, numerical analysis, and the emerging field of computing. ONR money helped support Project Whirlwind at MIT, the Institute for Numerical Analysis at UCLA, early stored-program machines, and studies of magnetic-core memory, transistors, and interactive displays. She argued that smaller, faster, cheaper computers had educational and commercial value as well as military use. A 1953 resolution of the American Mathematical Society credited her with “the most intelligent and wholehearted support” of basic research and declared that postwar American mathematics owed an “immeasurable debt” to the policies she conducted.
In 1953 Rees returned to Hunter College as dean of the faculty, a position she held until 1961. When the City University of New York was created she became its founding dean of graduate studies, charged with building doctoral programs from the strengths of the existing colleges. She later served as provost of the graduate division and, from 1969 to 1972, as president of the Graduate School and University Center. She retired as president emerita. In 1985 CUNY named its graduate library the Mina Rees Library, the first American library dedicated to a mathematician.
Rees was elected president of the American Association for the Advancement of Science for 1971, the first woman to hold that office in the nation’s largest scientific society. She had long served on its board. In 1962 she received the first Award for Distinguished Service to Mathematics from the Mathematical Association of America. Other honors included the Public Welfare Medal of the National Academy of Sciences in 1983, the IEEE Computer Society Pioneer Award in 1989, and some eighteen honorary degrees. She served on the National Science Board, advisory committees of the National Bureau of Standards and the National Science Foundation, and as a trustee of the American Mathematical Society.
In 1955 she married Leopold Brahdy, a physician born in Vienna; she was sometimes listed as Mina Rees Brahdy. She enjoyed oil painting, concerts, bird watching, travel, and cooking, and she insisted that mathematicians were “human beings with many interests outside mathematics.” She died on October 25, 1997, in New York City at the age of ninety-five.
Rees’s original research output was modest, yet her influence on American mathematics, computing, and graduate education was large. She moved easily between pure algebra, wartime applied work, federal science policy, and university administration. She helped establish the pattern of government support for basic research that characterized the postwar era, and she opened institutional doors for women without lowering standards. Colleagues observed that a concise account of her career read like a history of American mathematics in the middle decades of the twentieth century. That assessment remains fair. She understood that science required not only theorems but also money, organization, machines, and trained people, and she spent her working life supplying those necessities with unusual clarity and persistence.