Samuel Eilenberg

Samuel Eilenberg was a Polish-American mathematician, born in Warsaw in 1913, who co-founded category theory with Saunders Mac Lane and homological algebra. He also founded the field of algebraic automata in his work with Jesse B. Wright, and he identified a correspondence between varieties of regular languages and pseudovarieties of finite monoids, now known as Eilenberg's theorem. With Norman Steenrod he gave an axiomatic treatment of homology theory, and the Eilenberg-Steenrod axioms are named for the pair. He spent much of his career as a professor at Columbia University.