John L. Plyler was the son of John Robert and Mary (Earle) Plyler, born on January 12, 1894, in Travelers Rest, South Carolina. Plyler received a Bachelor of Arts degree from Furman University in 1913, an LL.B. from Harvard Law School in 1921, an LL.D. from Erskine College in 1939, and honorary Doctorate of Letters degrees from Wofford College in 1953 and Furman University in 1954.

Prior to his employment as Furman University president, Plyler served in the U.S. Army in WWI as a second lieutenant before attending Harvard Law School. Afterward he worked for the law firm of Haynsworth & Haynsworth, and taught in Furman's new Law School beginning in 1922, eventually becoming Dean of the Law School until it closed in 1932. Plyler was also an Instructor in Economics, 1936-38 and served on the Board of Trustees 1937-38. Plyler became a partner in the law firm of Mann & Plyler in 1925 which continued until he was elected Greenville County Judge in 1934. After serving four years he was elected to another four-year term, but was elected as Furman University President on December 15, 1938, and assumed the position on January 1, 1939.

Plyler served as president of Furman University between 1939 and 1964. Plyler died Friday, April 5, 1966 in Greenville, South Carolina at the age of 72.