History of the Roman Empire from this point on, leading his biographers to label him as insane. Most of what history remembers of Caligula comes from Suetonius, in his book "Lives of the Twelve Caesars". According to Suetonius, Caligula once planned to appoint his favourite horse Incitatus to the Roman Senate. He ordered his soldiers to invade Britain to fight the Sea God Neptune, but changed his mind at the last minute and had them pick sea shells on the northern end of France instead. It is believed he carried on incestuous relations with his three sisters: Julia Livilla, Drusilla and Agrippina the Younger. He
Holy Roman Emperor right to elect the King and future Emperor. The seven prince-electors are named in the Golden Bull of 1356: The Archbishop of Mainz, the Archbishop of Trier, the Archbishop of Cologne, the King of Bohemia, the Count Palatine of the Rhine, the Duke of Saxony and the Margrave of Brandenburg. After 1438, the Kings remained in the house of Habsburg and Habsburg-Lorraine, with the brief exception of Charles VII, who was a Wittelsbach. Maximilian I (Emperor 1508–1519) and his successors no longer travelled to Rome to be crowned as Emperor by the Pope. Maximilian, therefore, named himself Elected Roman Emperor