Sabre_of_Charlemagne
The so-called Sabre of Charlemagne (German: Säbel Karls des Großen) is an early sabre of Hungarian (Magyar) type (presumably made in the early 10th century) which has been exceptionally preserved (as opposed to recovered from the archaeological record) as part of the Aachen regalia of the Holy Roman Empire. Along with the rest of the imperial regalia from both Aachen and Nuremberg, it is now kept in the Hofburg Palace, Vienna.
The Sabre of Charlemagne is not to be confused with Joyeuse, another sword claimed to have been Charlemagne's personal weapon and used as regalia, but associated with the coronation of the French monarch rather than the Holy Roman Emperor.