years ago. It only existed for 51 years, 1867 to 1918.
It was staggeringly complex, with 14 official languages (Croatian, Czech, German, Hungarian, Italian, Lithuanian, Polish, Romanian, Ruthenian, Serbian, Slovak, Slovene, Ukrainian and Turkish), and over 1,000 dialects and sub-dialects spoken inside its maximal borders.
It only had two emperors the entire time (almost just one)
Emperor-King
18671916
Franz Joseph I
19161918
Karl I & IV
His Imperial and Apostolic Majesty,
Franz Joseph I,
By the Grace of God,
Emperor of Austria,
King of Hungary and Bohemia,
King [of Lombardy and Venice,] of Dalmatia, Croatia, Slavonia, Lodomeria and Illyria; King of Jerusalem etc., Archduke of Austria; Grand Duke of Tuscany and Cracow, Duke of Lorraine, of Salzburg, Styria, Carinthia, Carniola and of the Bukovina; Grand Prince of Transylvania; Margrave of Moravia; Duke of Upper and Lower Silesia, of Modena, Parma, Piacenza and Guastalla, of Auschwitz [Oświęcim] and Zator, of Teschen [Cieszyn/Těín], Friuli, Ragusa [Dubrovnik] and Zara [Zadar]; Princely Count of Habsburg and Tyrol, of Kyburg, Gorizia and Gradisca; Prince of Trent [Trento] and Brixen [Bressanone]; Margrave of Upper and Lower Lusatia and in Istria; Count of Hohenems, Feldkirch, Bregenz, Sonnenberg, etc.; Lord of Trieste, of Cattaro [Kotor], and in the Wendish Mark; Grand Voivode of the Voivodina of Serbia etc. etc.