Josephine Kopenhaver, painter, printmaker, and teacher, was born Josephine Young in Seattle, Washington on 9 June 1908. In the early 1920s she moved to Los Angeles, where she received her B.A. degree in 1928 from University of California Los Angeles and her M.F.A. degree in 1937 from the University of Southern California. She also studied with Millard Sheets at the Chouinard Art Institute in Los Angeles. In 1931 she wed Ralph Kopenhaver and thereafter used her husband's name. Her work is often signed Jo Kopenhaver.

Kopenhaver taught art for many years at Los Angeles City College and was secretary of the California Watercolor Society. She was a member of and exhibited with the California Watercolor Society, the Los Angeles Art Association, the Audubon Artists, the American Artists Congress, and the American Artists Professional League. Her work was also included in the an exhibition at the San Diego Fine Art Society; Allied Arts at the Los Angeles County Museum of Art, 1936; the Los Angeles County Fair, 1938; the Golden Gate International Exposition, 1939; as well as at the Oakland Art Gallery (now the Oakland Museum of California); the Santa Cruz Art League; the Foundation of Western Art; the Santa Barbara Museum of Art; the Pasadena Art Institute (now the Norton Simon Museum of Art); the Seattle Art Museum; and Los Angeles City College.

Her work was awarded prizes from the Women Painters of the West in 1940 and the California Watercolor Society in 1944, and she is represented in the Georgetown University Library, University Art Collection, Washington, D.C.

Josephine Young Kopenhaver died in Los Angeles on 4 December 1991.