Born in Delaware, Crumpler was raised partly by an aunt in Pennsylvania who cared for sick neighbours. She later moved to Massachusetts and spent years nursing before entering medical school in 1860.
The New England Female Medical College offered women an education focused strongly on women's and children's care. Crumpler graduated as the Civil War ended, when emancipation created enormous health needs but no equal medical system. In Richmond, Black patients frequently encountered physicians who refused to treat them and pharmacists who would not fill prescriptions from Black doctors.
Returning to Boston, she established practice in Beacon Hill and treated patients regardless of their ability to pay. Her later move to Hyde Park and the publication of her book show a life extending beyond the dramatic moment of graduation.