Charlemagne was not a German king.. He was king of the germans ;)
In Germany he's known as Karl der Große. Leader of the Franks. "Frank" being an oldish word for "free"...as in "Frank und Frei".
The Franks were a loose confederation of german tribes who gave France their name
His capital was Aachen and he was German :)
He was a frankish king exploiting the Germanic lands...
Which one doesn't! ;)
But he was also the one who sowed the seeds for later France, Germany and Italy.
One of the most important figures in european history!
Carolus Magnus or Karolus Magnus, meaning Charles the Great; possibly 742 - 28 January 814) was King of the Franks from 768 and Emperor of the Romans (Imperator Romanorum) from 800 to his death.
He expanded the Frankish kingdom into an empire that incorporated much of Western and Central Europe.
The EU is actually his empire second try. ;)