Theo Vennemann genannt Nierfeld (German: ['f?n?man]; born 27 May 1937 in Oberhausen-Sterkrade) is a German historical linguist known for his controversial theories of a "Vasconic" and an "Atlantic" stratum in European languages, published since the 1990s.He was professor of Germanic and theoretical linguistics at Ludwig Maximilian University, Munich from 1974 (retired 2005).