From 1922 to 1934 he studied theology and philosophy at the universities of Innsbruck and Oxford.

From 1935 to 1939, Neumann studied German and Nordic philology at the University of Marburg under Karl Helm, Walther Mitzka and Ludwig Wolff.

He received his Ph.D. with a thesis on the Eddas at Marburg in 1941 under the supervision of Helm and Wolff.

Since 1951, Neumann lectured in Germanic philology at the University of Göttingen.

In 1955 he was appointed a guest professor at the Free University of Berlin.