Dr. Euphemia Haynes is currently thought to be the first African-American woman to receive a Ph. D. in mathematics (Catholic University, 1943).
Evelyn Boyd Granville (Yale) and Marjorie Lee Browne (U. of Michigan) were both awarded doctorates in 1949. All three seem to have been unaware that they might be holders of any records. They merely were pursuing a love of mathematics.
Euphemia Haynes, earned her undergraduate degree from Smith College in 1914. She managed to complete her Ph. D. in mathematics 29 years years later at the age of 53 while working full time in demanding jobs. These positions included being Chair of the District of Columbia School Board.
These three women were true pioneers in the finest American tradition.
Photo courtesy of the Smith College Archives, Smith College