Mossell was born in 1856. His paternal great-grandfather was stolen from West Africa and brought to the United States as a slave.
Mossell’s parents moved from Baltimore to Hamilton, Ontario, Canada, where he was born and lived with his five siblings and parents until they relocated to upstate New York during the Civil War.
In the town of Lockport, near Niagara, N.Y., Mossell’s father established a successful brick manufacturing business and was able to send Mossell’s oldest brother Charles to college at Lincoln University.
Nathan’s schooling became irregular when he began working at his father’s brickyard when he was just 9 years old. At one point, Nathan didn’t attend school at all and worked full-time for his father. Then, at the age of 15, he enrolled at Lincoln University, where he completed four years of prep school in three years, followed by four years of college. After graduating from Lincoln, Mossell entered Penn’s Medical School and took second honors in his class when he graduated in 1882.
Because black people had a difficult time securing internships at the time, Mossell had to travel to England to intern at the Guy’s, Queen’s College, and St. Thomas hospitals in London.
In 1888, when he returned to Philadelphia, Mossell, after some opposition because of his race, was elected to the Philadelphia Medical Society as its first African-American member.
Mossell operated his medical practice at 924 Lombard St. and immediately had an impact on medical practices in Philadelphia and the position of African Americans in the city and across the United States.
His other accomplishments include his work as a civil rights leader. Mossell was the founder of the Philadelphia branch of the NAACP and the Frederick Douglas Memorial Hospital and Training School, which treated African Americans and also offered internships to black doctors and nursing training to black women.
Mossell’s wife, Gertrude, was a teacher in Philadelphia and Camden, N.J., and also a professional writer and editor.
The Mossells were part of gifted extended families.
Aaron’s daughter, Nathan’s niece, was Sadie Tanner Mossell, the civil rights leader who earned a Ph.D. from Penn in economics and is also the first African-American woman to graduate from Penn Law School.
For more information about this and other historical events at Penn, visit the University Archives online.