Homer Lumpkin Barker was born 3 August 1884 in Heard County, Georgia, the son of John W. Barker and Ida M. (Tomlin) Barker. He was thirteen years old when his father died. As a boy he had attended the Union Grove School in the Rockalo District in Heard County and also the Franklin Collegiate Institute. He had learned the trade of carpenter and did contracting and taught school in order to further his education. He paid his own way through medical school. While an intern in the Augusta, Georgia, hospital, he was given charge of the department of contagious diseases. During the years 1910-1911 he supervised 208 smallpox cases. He graduated from the University of Georgia Medical College in 1912 with high honors, standing fourth in a class of forty-two.

Dr. Barker remained at the Augusta Hospital for thirteen months after his graduation. On January 7, 1913, he began to practice medicine at Carrollton, Georgia, being a general practitioner, but also specializing in genital and venereal diseases and surgery. He was a president of the City Board of Health of Carrollton, was county physician of Carroll County, and served as Chief of Staff at Tanner Memorial Hospital. Dr. Barker was also a member of the Carroll-Douglas-Haralson Medical Society, Georgia Medical Society, the American Medical Association, and the American Academy of General Practitioners. During World War I he served as a First Lieutenant in the Medical Corps.

Dr. Barker was a member of the Masonic Lodge, the Shriners, the Independent Order of Odd Fellows, the Woodmen of the World, and was a charter member of the Carrollton Lions Club, serving that organization at various times as president, treasurer, and secretary. In 1939 he was elected Vice-Chairman of the Lions Club International Board of Governors and in 1949 a Director of Lions International. He was a member of the First Methodist Church, a past teacher of the Men's Bible class, and an honorary member of the Board of Stewards. He served on the Draft Board and was chairman of the Bond Committee in World War II. He served on the Carrollton Board of Education for 18 years. He was a member of Sunset Hills Country Club. Dr. Barker received numerous awards. In 1962, he was chosen as Carrollton's Man of the Year. He died in September 1963 in Carrollton, Georgia.