Ackermann was born on March 29, 1896 in Schönebecke (then Altena district, now part of Herscheid municipality), Germany, and received his doctoral degree in 1925 with his thesis *Begründung des "tertium non datur" mittels der Hilbertschen Theorie der Widerspruchsfreiheit*, which was a consistency proof of arithmetic without induction. From 1929 until 1948 he taught at the Arnoldinum high-school in Burgsteinfurt, and afterwards till 1961 in Lüdenscheid. He was also a corresponding member of the Akademie der Wissenschaften (*Academy of Sciences*) in Göttingen, and was an honorary professor at the Universität Münster (Westphalia).

He wrote *Grundzüge der Theoretischen Logik* (*Fundamentals of the Theoretical Logic*) with David Hilbert, dealing with Entscheidungsproblem and also constructed consistency proofs for set theory (1937), full arithmetic (1940), type-free logic (1952) and a new axiomatization of set theory (1956). He wrote the book *Solvable cases of the decision problem* (North Holland, 1954).

Wilhelm Ackermann died in Lüdenscheid, Germany on December 24, 1962.