His son, John Wesley Cromwell Sr., went on to become a prominent lawyer, historian, journalist, and civil rights activist; he also published The People's Advocate in the late 19th century.

[3][4] After graduating from Dartmouth, Cromwell Jr. returned to Washington, D.C., where he taught German, Latin, and mathematics at Paul Laurence Dunbar High School from 1907 to 1930.

These experience requirements often posed a barrier for Black Americans seeking to enter the profession due to limited access to employment opportunities within established accounting firms.

[1][2][3][4][6] After receiving his CPA license, Cromwell continued to teach while also establishing his own accounting practice in Washington, D.C. His clientele primarily consisted of Black-owned businesses and organizations in the Washington, D.C. area, including churches, restaurants, and funeral homes.

Their daughter, Adelaide M. Cromwell, pursued a career in academia, becoming a professor of sociology at Boston University.