What countries did the Hapsburg Empire rule?
In the period 1866-1918 the Hapsburg Empire consisted of the whole of these countries: Austria, Hungary, Czech Republic, Slovakia, Slovenia, Croatia. It also included substantial areas of what is now Romania, Poland, Ukraine. It also included small areas of what is now Italy and Serbia. From 1878-1918 it included Bosnia-Herzegovina.
The Hapsburg Empire held, at one point or another, the thrones of the Archduchies of Upper and Lower Austria, the Duchies of Styria, Carinthia, Carniola, Serbia, Milan, Parma and Bukovina, the County of Tyrol, the Grand Duchy of Salzburg, the Kingdoms of Bohemia (including the 'Lands of the Bohemian Crown), Hungary, Naples, Sardinia, Sicily, Galicia & Lodomeria, Dalmatia, Lombardy-Venitia, the Banat of Temeswar, the Vogvodina of Serbia & Tamis Banat and the Grand Principality of Transylvania along with the Adriatic Port of Trieste and the territories of Istria, Gorizia, Gradisca, the Vorarlberg, the Vorlande, the Austrian Netherlands, Oltenia (also known as Grand-Voivodate or Valachia Ceasarea), new Galica (including, after it's incorporation, Krakow), Venetia, the Raska Region and Bosnia and Herzegovina. Various members of the dynasty also ruled Spain (Castille & Aragon and their territories), Tuscany, Wurzburg, Vorlande, Modena, the Duchy of Parma and the Second Mexican Empire. Napoleon I of France and Peter I of Brazil were married to members of the Hapsburg dynasty whilst on the throne.