Gordon Chenoweth Sauer, M.D. was born in Rutland, Illinois on August 14, 1921 to Fred W. Sauer (1887-1961) and Gweneth Eleanor Chenoweth (1892-1989). Shortly after his birth, the family moved to LaSalle, Illinois, where Sauer was raised.

Sauer attended Northwestern University from 1939 to 1942. Upon graduating, he attended medical school at the University of Illinois at Chicago from 1942 to 1945. He completed his internship at Cook County Hospital in 1946. During World War II, Sauer served as a captain in the Army, working at the Public Health Service in Charleston, West Virginia. In 1951, he completed his residency in dermatology and syphilology at the Skin and Cancer unit at New York University-Bellevue Medical Center.

Sauer was active in publishing research throughout his medical career. He wrote and published the noted medical school textbook, "The Manual of Skin Diseases", through its 7th edition in 1996. He also wrote "Teen Skin" in 1965. He was the editor of the "Jackson County Medical Bulletin" from 1967 to 1969, and contributed numerous articles to professional journals. For many years Sauer published "Sauer Notes," a monthly column in the "Schock Newsletter of the American Academy of Dermatology".

In addition to his full-time medical practice and his writing, Sauer taught at both the University of Missouri and the University of Kansas. He was associated with the University of Kansas School of Medicine from 1951 on. He was the head of the Dermatology Department from 1958 through 1970 and became clinical professor emeritus in July 1993. Sauer was the acting head of the dermatology section at the University of Missouri at Columbia from 1955 to 1959. He was also a lecturer in medicine at the University of Missouri-Kansas City School of Medicine from 1971-1974 when he began serving as clinical professor.

Sauer had a lifelong devotion to the study of John Gould, the 19th-century British nature artist and ornithologist. Sauer's love for Gould's work began as a teenager when his mother purchased a set of Gould prints from an antique dealer. Sauer collected Gould's works and became the preeminent biographer of John Gould. Beginning in 1948, Sauer published numerous articles and books about Gould. In 1982 he published "John Gould the Bird Man: a Chronology and Bibliography", which has become the leading biography on Gould. Sauer also published "John Gould Bird Print Reproductions" (1977), "John Gould's Prospectuses and List of Subscribers to his Work on Natural History" (1980), "John Gould the Bird Man: Associates and Subscribers" (1995), "John Gould the Bird Man: Bibliography" (1996), "John Gould the Bird Man: Correspondence", Vols. 1-5 (1998, 1998, 1999, 2001, 2003).

With an interest in nature from youth, Sauer was active in naturalist organizations throughout his life. During his college years he was a naturalist guide at Starved Rock State Park, and contemplated becoming a forest ranger instead of a medical doctor. Sauer was on the Board of Directors of the Nature Conservancy of Missouri from 1984-1991. He became an honorary Life Member of the Nature Conservancy in 1986. Sauer was a member of the American Ornithological Union, the Wilson Ornithological Society, the Royal Australasian Ornithologists Union, and the Society of Bibliography of Natural History. He was an avid bird watcher, particularly at his farm in Cass County, Missouri.

Sauer married Mary Louise Steinhiller in 1944. The couple had four children, Elisabeth, Gordon Jr., Margaret, and Amy. In 1982, Sauer married Marion Green (1927-2003). Gordon Sauer died September 1, 2003.