Born on July 19, 1924, in Osceola, Nebraska, Stanley Knapp Hathaway received his B.A. (1948) and his LL.B. (1950) from the University of Nebraska. During the World War II, he served in the United States Army Air Force from 1943 to 1945. Hathaway practiced private law after the war in Torrington, Wyoming, and became the prosecuting attorney in Goshen County, Wyoming, in 1954.

He was elected to two terms as governor of Wyoming, serving from 1967 to 1975, and served as both a member of the Executive Committee of the National Governors' Conference (1968-1969) and chairman of the Committee on Natural Resources and Environmental Management (1973-1974). Hathaway was vice chairman of the Western Governors' Conference from 1969 to 1970 and chairman from 1970 to 1971.

President Gerald Ford nominated him on April 4, 1975, to become the secretary of the Interior, succeeding Rogers C. B. Morton, whom Ford nominated to become secretary of Commerce. Hathaway served in that post from June through July 1975, when he resigned due to ill health. Hathaway continued his law practice in Cheyenne, where he died on October 4, 2005.