In a memorable duel at Aix-la-Chapelle (A.D. 820), before the emperor Lewis the Pious, his biographer observes,
secundum legem propriam, utpote quia uterque Gothus erat,
equestri pugnâ [proelio] congressus est (Vit. Lud. Pii. c.
33, in tom. vi. p. 103).
Ermoldus Nigellus (l. iii. 543-628, in tom. vi. p. 48-50), who describes the duel admires the ars nova of fighting on horseback, which was unknown to the Franks.