That achievement merely capped off a remarkable life. Born in 1845 to free blacks in Boston, Mahoney was the first black person to study and work as a professionally trained nurse in the United States, graduating from the New England Hospital for Women and Children’s nursing school in 1879.
She worked most of her career as a private care nurse, mostly for wealthy white families. She became one of the first black members of the Nurses Associated Alumnae of the United States and Canada and in In 1908 co-founded the National Association of Colored Graduate Nurses. She was inducted into the Nursing Hall of Fame in 1976 and the National Women's Hall of Fame in 1993. She died in Boston on January 4, 1926, at the age of 80.