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.
Ostrogothic Ravenna
In 476 the last emperor of the Western Roman Empire, Romulus Augustus, was forced to abdicate under invasions by Goths led by Odovacar. Upon the sacking of Rome by these Goths, Odovacar declared himself King of Italy and was able to conquer the peninsula as well as much of the "Dalmatian coast". Odovacar drew the ire of the imperial court at Constantinople as "a barbarian, a non-Roman, had deposed the Roman emperor in the original heartland of the empire. He had taken on the hated royal title and was getting ready to rule in the emperor’s place..." Odovacar, however, issued his coinage in the name of the emperor Nepos, whom Constantinople had never removed its recognition of when Romulus had assumed the imperial title therefore painting himself as merely overthrowing a previous usurper to the imperial throne.