Weimar culture was conceived outside the schools and universities and it never penetrated the academic establishment to any depth. The opposition of so many academics to the Weimar Republic and all it stood for does not imply that the great majority of professors were Nazis or Nazi sympathizers. Attacks on Jewish students occurred at various German universities after 1919; they were neither widespread nor large-scale in comparison with the academic pogroms which took place in Austria and some East European countries. Germany had been one of the cradles of modern sociology and the years just before and after the First World War were the most productive in the history of discipline. The first convention of German sociologists took place in Frankfurt in 1910 with Georg Simmel, Werner Sombart, Ferdinand Tonnies, Max Weber and Ernst Troeltsch among the principal speakers. Sombart had begun his career as a Marxist tout court, but in later years became the protagonist of a 'German Socialism'.