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.
Constantine XI Palaiologos
Constantine XI Dragases Palaiologos, Latinized as Palaeologus (, "Kōnstantinos XI Dragasēs Palaiologos"; 8 February 1405 – 29 May 1453) was the last reigning Roman and Byzantine Emperor, ruling as a member of the Palaiologos dynasty from 1449 to his death in battle at the fall of Constantinople in 1453.