Herbert John Ryser (July 28, 1923 – July 12, 1985) was a professor of mathematics, widely regarded as one of the major figures in combinatorics in the 20th century.

[3] His doctoral thesis "Rational Vector Spaces" was supervised by Cornelius Joseph Everett, Jr. and Cyrus C.

)[5] After his Ph.D., Ryser spent a year at Princeton's Institute for Advanced Study, then joined the faculty of Ohio State University.

[6] His doctoral students include Richard A. Brualdi, Clement W. H. Lam, and Marion Tinsley.

[7] The Journal of Combinatorial Theory, Series A denoted two issues after Ryser's passing as the "Herbert J. Ryser Memorial Issue", parts 1 and 2.