E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Rome of the West.
Aachen, or Aix la Chapelle, the favourite city of Charlemagne, where, when he died, he was seated, embalmed, on a throne, with the Bible on his lap, his sword (La Joyeuse) by his side, the imperial crown on his head, and his sceptre and shield at his feet. So well had the Egyptians embalmed him, that he seemed only to be asleep.