Austria's exclusion from Germany caused many Austrians a problem with their national identity and prompted the Social Democratic Leader Otto Bauer to state that it was "the conflict between our Austrian and German character". The Austro-Hungarian Empire caused ethnic tension between the German Austrians and the other ethnic groups. Many Austrians, especially those involved with the pan-German movements, desired a reinforcement of an ethnic German identity and hoped that the empire would collapse, which would allow an annexation of Austria with Germany.