The United States of Greater Austria (German: Vereinigte Staaten von Groß-Österreich) was a proposal, conceived by a group of scholars surrounding Archduke Franz Ferdinand of Austria, that never came to pass. This specific proposal was conceived by the lawyer and politician Aurel Popovici in 1906 and aimed at federalizing Austria-Hungary to help resolve widespread ethnic and nationalist tensions.
As the twentieth century started to unfold, the greatest problem facing the dual monarchy of Austria-Hungary was that it consisted of about a dozen distinctly different ethnic groups, of which only two, the Germans and Hungarians (who together accounted for about 44% of the total population), wielded any power or control. The other ethnic groups, which were not involved in the state affairs, included Slavic (Croats, Czechs, Poles, Ruthenians, Serbs, Slovaks, Slovenes and Ukrainians) and Romance peoples (Italians, Romanians). Among them, only Croats had limited autonomy in the Kingdom of Croatia and Slavonia. The idea of the Dual Monarchy system of 1867 had been to split the previous Austrian Empire into two realms, one German-dominated, the other Hungarian-dominated. However, after various demonstrations, uprisings and acts of terrorism, it became readily apparent that the notion of two ethnic groups dominating the other ten could not survive in perpetuum.