He taught at a number of universities, worked on the staffs of several museums, and served as curator of the U.S. Capitol, 1976-1980.
[1] He was born in Philadelphia, Pennsylvania, the son of Thorsten and Amy Anderson Sellin.
[5] His research into the influence of France on 19th-century Philadelphia artists – notably Joseph A. Bailly, Mary Cassatt, Eakins, and Howard Roberts – culminated in a 1973 exhibition at the Philadelphia Museum of Art.
[1] He moved to Washington, D.C. in 1971, to work as a research fellow at what became the Smithsonian Museum of American Art.
[1] He published numerous articles on American artists, and worked as an independent curator and consultant.