Descended from Theophile Bruguier and Yankton ItanchanWar Eagle and Struck By The Ree, Leonard spent his early childhood at Greenwood on the Yankton Reservation and his later school years in Yankton, South Dakota where he graduated from high school.

Leonard earned a Bachelor of Arts degree in American History and a Masters of Public Administration from the University of South Dakota. While at the University, he completed a summer seminar in public policy from the University of Minnesota's Hubert H. Humphrey Institute and won the History Alumni and the A. B. Gilfillian award for creative writing. Named twice as a fellow in the Public Service Fellowship Program, he also earned a Smithsonian Institution Fellowship and served as Research Associate for the American Indian Research Project/South Dakota Oral History Project at the University of South Dakota.

Leonard is a member of the International Association of Machinists and Aerospace workers, Vietnam Veterans of America, Custer Battlefield Indian Memorial Committee, Phi Alpa Theta, Organization of American Historians, Western History Association, Southern Historical Association, South Dakota Historical Society, Center for Western Studies at Augustana, and the South Dakota Indian Education Association.

His duties as Institute Director include administrative supervision, development and direction of American Indian related projects and activities, and programs involving the University of South Dakota. Other responsibilities are the promotion of inter-University lines of communication among Indian faculty and staff, recruitment and retention of Indian students, and strengthening of relations with tribes, tribal colleges, and other Indian organizations throughout the state and region.

The new director is a published author and editor of several books and scholarly articles. He hopes to attract other Indian writers and to serve as a clearing house for Indian literature.