Complex sentence: This name, however, was prohibited by The Entente, they also crushed the resolution of the Constituent National Assembly in Vienna that "German-Austria" was to be part of the German Weimar Republic.
Split into simpler sentences: This name, however, was prohibited by The Entente. They also vetoed a resolution of the Constituent National Assembly in Vienna that "German-Austria" was to be part of the German Weimar Republic.