BALTIMORE — Mostly undiscovered and unknown, the history of African-American owned cooperatives in the United States has shown that they were pivotal in helping create wealth during times of inequality.

Speaking at the African-American Credit Union Coalition's annual meeting here, Dr. Jessica Gordon Nembhard, assistant professor and economist at the University of Maryland, College Park, shared research she has uncovered on several successful African-American co-ops. Among them, the Chesapeake Marine Railway and Dry Dock Company formed in 1865 at the end of the Civil War. The co-op existed until 1883 and served stevedores and caulkers. At one point it raised $40,000 selling 8,000 shares at $5 a share and in 1871 was able to issue a $14,000 dividend to its members.

Nembhard, who is currently working on a book on African-American co-ops, also discovered the Cooperative Society of Bluefield Colored Institute, a school supply group that used some of its profits to provide scholarships. In the 1930s, the Consumers Cooperative Trading Company was owned by more than 100 members and in 1936 became the largest grocery business operated by African-Americans in the United States, she said.