ABGILLUS, JOHN, surnamed Prefler John, was son to a king of the Frisii; and, from the austerity of his life, obtained the name of Prefler, or Priest. He attended Charlemagne in his expedition to the Holy Land; but instead of returning with that monarch to Europe, it is pretended that he gained mighty conquests, and founded the empire of the Abyssines, called, from his name, the empire of Prefler John. He is said to have written the history of Charlemagne's journey into the Holy Land, and his own into the Indies; but they are more probably trilling romances, written in the ages of ignorance.