George McKenzie Roberts was born on December 28, 1886, in Vergennes, Vermont; his parents were George Simon Roberts and Florence Louise McKenzie. He was educated formally only up to the eighth or ninth grade, then began working for General Electric in 1901 at the age of 15. The family lived in Glenville, Schenectady, New York, from at least 1900 to 1905. On October 20, 1909, he married Anne Edith Campbell in New Haven (or Addison), Vermont. The couple had no children and are believed to have later divorced. In June 1917, George registered for the draft in Schenectady, New York.

From 1919 until 1953, he worked for the International General Electric Company, Inc., in New York City as Credit Manager, Assistant Treasurer, and Treasurer. He also worked as treasurer and one of the directors of Electrical Export Corporation, and was chief of the Foreign Trade Branch of the U.S. Office of Price Stabilization in Washington, D.C., from 1951 until his retirement in 1953. In 1942, he registered for the draft to serve in World War II. In 1943, on November 22, George married Grace Agnes Rhodes Perkins (or Ruth G. Rhodes) in Reno, Nevada; this marriage also seems to have ended in divorce, with no children. In 1947, Roberts emigrated to Rio de Janeiro, Brazil, with his wife. During the course of his career, he had also served as a director of the New York Board of Trade, as well as of other business clubs and associations, from 1920 to 1950.

After retirement, Roberts took up genealogical research, publishing two serial-running genealogies in the New York Genealogical and Biographical Record: "The Druse Genealogy," from 1938 to 1939, and "The Denslow Family in America," from 1946 to 1950 and again from 1957 to 1959. His research resulted in a number of vital, cemetery, land and tax, and probate records, census enumerations, and Revolutionary soldiers' records related to the town of Enfield, New Hampshire; these also appeared in the N.Y.G. & B. Record, in 1957. He also published an article, "On the Marring of Research Sources," in The American Genealogist in October 1955, and his Ancestor Table was featured in that same issue.

George was elected a Fellow of The American Society of Genealogists in 1950. He also belonged to many historical associations, including the New England Historic Genealogical Society; the New York Genealogical and Biographical Society; Sons of the American Revolution (for which he served as Treasurer General and Genealogist General); the Society of Colonial Wars in the State of New York; the New York State Historical Association; the Vermont, New Hampshire, and Connecticut Historical societies; Descendants of the Illegitimate Sons and Daughters of the Kings of Britain; and the Denslow Family Association. Roberts died on April 7, 1980, in San Francisco, California, at the age of 93.