Greensville S. Dowell, surgeon, teacher, and editor, son of James and Frances (Dalton) Dowell, was born in Albemarle County, Virginia, on September 22, 1822. The family moved to Panola County, Mississippi, in 1837. Before studying at the medical department of the University of Louisville in 1845–46, Dowell lived and studied medicine with his physician brother, Alep Dowell, in Raleigh, Tennessee. He enrolled in Jefferson Medical College in Philadelphia and received his M.D. degree in 1847. He then set up practice in Como, Mississippi, where he lived until 1852. After a short practice in Memphis, Tennessee, he moved to Texas in September 1853 and settled in Sandy Point, Brazoria County. During the Civil War he served as a surgeon with the Confederate States Army in Galveston.
On July 17, 1865, Dowell and a group of local physicians formed the Galveston Medical Society. In November Galveston Medical College, the first medical school in Texas, was organized by the trustees of Soule University, and Dowell was appointed professor of anatomy. The same year Dowell began making plans to publish the first medical periodical in Texas, the Galveston Medical Journal, which began publication in January 1866.
In 1867 Dowell was appointed professor of surgery, and later that year he was elected dean of the college. When Soule University closed Galveston Medical College and moved to Louisiana in 1873, Dowell and J. M. Callaway founded Texas Medical College and Hospital, where Dowell continued to teach surgery until his death.
In addition to his teaching and editing responsibilities, he published two books and about fifty articles. The surgical operation he devised for the cure of hernia by means of subcutaneous stitches was well known among his contemporaries; Dowell described the procedure in his monograph, A Treatise on Hernia (1876). He also designed several surgical instruments, including needles for repairing hernia and ligating varicose veins, and several kinds of forceps and specula. He was regarded as an authority on yellow fever, and he often traveled to epidemic-stricken cities to treat victims. His Yellow Fever and Malarial Diseases (1876) includes an account of his own experiences as well as reports written by other Texas physicians.
Dowell was a member of the American Medical Association, the Texas State Medical Association (see TEXAS MEDICAL ASSOCIATION), and the Galveston Medical Society; he was an honorary member of the Boston Gynecological Society and the New York State Medical Society. He married Sarah Zalinda White in 1849 at Como, Mississippi, and they had three children. In 1868, after his first wife's death, Dowell married Laura Baker Hutcheson, widow of John William Hutcheson, of Galveston. He died in Galveston on June 9, 1881, and is buried in Evergreen Cemetery.