Emperor - the male ruler of an empire

Charlemagne, Charles the Great, Charles I - king of the Franks and Holy Roman Emperor; conqueror of the Lombards and Saxons (742-814)

Charles I, Charles II, Charles the Bald - as Charles II he was Holy Roman Emperor and as Charles I he was king of France (1630-1685)

Ferdinand I - Holy Roman Emperor and king of Hungary and Bohemia (1503-1564)

Ferdinand II - Holy Roman Emperor and king of Bohemia and Hungary who waged war against Protestant forces (1578-1637)

Ferdinand III - Holy Roman Emperor and king of Hungary and Bohemia who signed the Peace of Westphalia ending the Thirty Years' War (1608-1657)

Emperor Francis II, Francis II - the last Holy Roman Emperor (1768-1835)

Barbarossa, Frederick Barbarossa, Frederick I - Holy Roman Emperor from 1152 to 1190; conceded supremacy to the pope; drowned leading the Third Crusade (1123-1190)

Holy Roman Emperor Frederick II, Frederick II - the Holy Roman Emperor who led the Sixth Crusade and crowned himself king of Jerusalem (1194-1250)

Otho I, Otto I, Otto the Great - king of Germany and Holy Roman Emperor (912-973)