[1] Walker was the founding president of the Afro-American Historical and Genealogical Society (National), which grew to 23 chapters across the United States by 1999.
[3] Walker worked for thirty years at the National Archives and Records Administration where he worked as a genealogist, research consultant, Supervisor of Military Records, Director of Local History and Genealogical Programs, and Assistant Director of the Institute of Genealogical Research at American University.
He was a specialist on black records that including information on birth, death and even the sale and transfer of slaves.
[2] He helped numerous people trace family members of African Americans whose ancestors were brought as slaves.
Throughout his life, he was a popular lecturer, teacher and research consultant on projects pertaining to black and ethnic genealogy.