Joseph Lynn Clark, teacher, administrator, and author, was born in Thorp Spring, Texas, on July 27, 1881, the son of Ella Blanche (Lee) and Randolph Clark and nephew of Addison Clark. During his undergraduate days at Texas Christian University, he played baseball and assisted in the organization of the Texas Intercollegiate Athletic Association, the state's first intercollegiate sports organization. He graduated from TCU in 1906. From 1906 to 1909 he was an instructor in history and English at Add-Ran College and in 1909–10 an instructor at John Tarleton College (now Tarleton State University). He attended summer sessions at the University of Virginia in 1907 and at the University of California in 1915; he also did graduate work at Columbia University in 1917 and at the University of Texas in 1927–28 and 1932–33. He was married to Sallie Frances Chism on August 28, 1913.
In 1910 Clark was named secretary to Harry F. Estill, president of Sam Houston Normal Institute (now Sam Houston State University), and was soon given the additional duties of registrar, purchasing agent, bookkeeper, and librarian. He taught history at Sam Houston and was named head of the history department there in 1916. He wrote two school textbooks, A New History of Texas (1928) and The Story of Texas (1932); he also wrote, with Elton M. Scott, The Texas Gulf Coast (1955). His book Thank God We Made It! (1969) was an account of his family's role in higher education in Texas. Clark was one of the organizers and second president of the Texas College Classroom Teachers Association (later renamed the Texas Association of College Teachers). He was a longtime member, vice president, and fellow of the Texas State Historical Association. He was a cofounder and member of the Texas Commission on Interracial Cooperation, and it is possible that his was the first college course offered in Texas on race relations. Clark died in Houston on September 13, 1969, and was buried in Huntsville.