That the high position attained by those sultans did not influence them against according their protection to Christian potentates, is evident from the intimate relations that existed between themselves and the kings or emperors of Abyssinia, among whom should certainly be included “Prester John, in enclosed Rumany”.
It is now generally admitted that Marco Polo, with his usual good faith, stated the precise truth in affirming that in his time, one George, a descendent of Prester John, became the governor of a province as a vassal of China. This prince professed the Roman Catholic faith, instead of Nestorianism as did his grandfather Ovang Khan, chief of the Keraits, and not, as Oppert has sought to prove (_Der Presb. Johannes in Sage und Gesch._, etc., Berlin, 1864) of the Gour Khan of the Karakhitaians mentioned by Rubruquis. In either case it is pretty certain that so soon as European intercourse with the interior of Asia decreased, the existence of a Christian state on the Nile, to the south of Egypt, became more generally known; a state to which Haythoun, the Armenian historian, had already directed the Pope’s attention (_De Tartaria_, c. 57, apud Webb, _A Survey of Egypt and Syria_, etc., 394), and it thereafter became the custom to metamorphose the Christian monarch of the Nubians and Abyssinians into Prester John. Like Schiltberger, De Lannoy (_Voy. et Ambass._, 93) knew of no other Prester John, and far from admitting his dependance on the sultan, a condition to be inferred by the title of protector attributed to the latter by Schiltberger, the knight implies that it was rather the sultan who was in a state of dependance on Prester John, in whose power it lay to “destourber le cruschon” of the Nile, which he certainly would have done, but for the fear of victimising the many Christians in Egypt.
In another chapter, De Lannoy terms these Christians “Christians of the girdle”, a name that was applied, says his commentator (Webb), in consequence of a law promulgated A.D. 856 by the caliph Motonakek, which prescribed that Jews and Christians should wear a broad leathern girdle. It appears, however, that in course of time the Nestorians and Jacobites also became subject to the same law, and this accounts for the expression, “Prester John, in enclosed Rumany”, which, if intended for Abyssinia, a country mistaken by Marco Polo and De Lannoy for that of the Brahmins, would indicate that the former was inhabited by the Christians of the girdle. (De Lannoy styles the primate of the Copts, the primate of India.) That they were believed to be in Abyssinia is proved in the following lines from Juan de la Encina’s narrative of his journey to Jerusalem in the year 1500.