George Green Shackelford was a professor of history at Virginia Tech. He also was a historical preservation expert and specialist in the age of Washington and Jefferson in Virginia history. In 1985, he received an award from the Virginia Chapter of the American Institute of Architecture in historic preservation.

Shackelford attended the Woodberry Forest School, Columbia University, and then the University of Virginia for his Ph.D. He also earned certificates from the Attingham Summer School and Institute of Historical and Archival Management.

In 1942, Shackelford received his commission in the Naval Reserve and served in anti-submarine warfare in the Atlantic and Pacific. He was a Lieutenant by the end of his service.

Before Shackelford taught at Virginia Tech from 1954 to 1986, he taught at Birmingham Southern College from 1948 to 1949 and worked as a research fellow at the Virginia Historical Society. From 1963 to 1964, Shackelford spearheaded the restoration of Smithfield Plantation. In 1967, he worked as a historical consultant to the Westmoreland David Memorial Foundation for Morven Park in Leesburg, Virginia.

Shackelford was also a prolific author. He wrote five books, including and . He also wrote many articles and was the co-editor of the .

Throughout his career, Shackelford was active in numerous associations and boards: He was the President of the Monticello Association from 1969 to 1971. He was on the board of directors for Association for the Preservation of Virginia Antiquities (APVA; now Preservation Virginia), and was the President of the Montgomery Branch of the Association for the Preservation of Virginia Antiquities in 1975. He was a member of the Board of Advisors of the National Trust for Historical Preservation from 1976 until 1979. He was a member of the Virginia Commission on the Bicentennial of the United States Constitution from 1987 until 1992. He was the President of the Southwest Virginia Branch of the English Speaking Union.