 Evidence for any political active role played by a 'Bayreuth Circle' as a group is therefore highly contentious.Amongst those often listed as 'members' of a Hitlerian Bayreuth Circle are Cosima Wagner (d. 1930), second wife of the composer, Winifred Wagner, wife of the composer's son Siegfried, and H. S. Chamberlain.None of the Wagners, however, played any personally active role in the Nazi movement, although Hitler was undoubtedly influenced by Chamberlain's "Foundations of the Nineteenth Century".