In 1874, Wagner finally completed his monumental opera cycle 'Ring of the Nibelung' – 25 years in the making. In that year, Germans were attempting to forge a national identity from their mythic past, and the rest of Europe was trying to cope with the implications of Darwin's 'Origin of Species' and Marx's 'Das Kapital'. Wagner's music had a grim legacy: the Nazis admired it for aesthetic reasons and for the composer's extreme racist views.