Walther Franz Anton von Dyck (6 December 1856 – 5 November 1934), born Dyck (German pronunciation: [diːk]) and later ennobled, was a German mathematician. He is credited with being the first to define a mathematical group, in the modern sense in (Dyck 1882). He laid the foundations of combinatorial group theory, being the first to systematically study a group by generators and relations.
Von Dyck was a student of Felix Klein and served as chairman of the commission publishing Klein's encyclopedia. Von Dyck was also the editor of Kepler's works. He promoted technological education as rector of the Technische Hochschule of Munich. He was a Plenary Speaker of the ICM in 1908 at Rome.
Von Dyck is the son of the Bavarian painter Hermann Dyck.
The Dyck language in formal language theory is named after him, as are Dyck's theorem and Dyck's surface in the theory of surfaces, together with the von Dyck groups, the Dyck tessellations, Dyck paths, and the Dyck graph.
O'Connor, John J.; Robertson, Edmund F., "Walther von Dyck", MacTutor History of Mathematics Archive, University of St Andrews
Walther von Dyck at the Mathematics Genealogy Project