Flags of the Holy Roman Empire
In 1804, Napoleon Bonaparte declared the First French Empire. In response to this, Emperor Francis II of the Habsburg dynasty declared his personal domain to be the Austrian Empire and became Francis I of Austria. Taking the colours of the banner of the Holy Roman Emperor, the flag of the Austrian Empire was black and gold. Francis II was the last Holy Roman Emperor, with Napoleon forcing the empire's dissolution in 1806. After this point, these colours continued to be used as the flag of Austria until 1918.
Frederick II, Holy Roman Emperor
Unlike most Holy Roman emperors, Frederick spent few years in Germany. In 1218, he helped King Philip II of France and Odo III, Duke of Burgundy, to bring an end to the War of Succession in Champagne (France) by invading Lorraine, capturing and burning Nancy, capturing Theobald I, Duke of Lorraine and forcing him to withdraw his support from Erard of Brienne-Ramerupt. After his coronation in 1220, Frederick remained either in the Kingdom of Sicily or on Crusade until 1236, when he made his last journey to Germany. He returned to Italy in 1237 and stayed there for the remaining thirteen years of his life, represented in Germany by his son Conrad.