Carignano Portolan Map (1305-1327)Carignano was known primarily as a cartographer and geographer, but he also wrote a now-lost treatise on Ethiopia based on an alleged meeting in Genoa with the Ethiopian embassy that traveled to Europe in 1306.
A summary of the long-lost commentary to the map can be found in Jacopo Filippo Foresti’s Supplementum Chronicarum.
Carignano's Portolan Map, based in part from the information he gleaned from the Ethiopian embassy, is the first known document to correctly situate the "black Christians" of Abyssinia/Ethiopia between the Blue and White Nile. According to Salvadore, "his was the first map to abandon the copycat style of mapmaking typical of medieval Europe, which simply proposed again and again geographical knowledge that originated in antiquity" (p. 602).
On the map, Carignano describes the land of Prester John
thusly (165):
"Prester John is set over that people [Ethiopians] as patriarch; and he says that under him are 127 archbishoprics, each of which has 20 bishops. Those who are to be reborn they baptize in the Roman manner…it is said that their emperor is most Christian, to whom 74 kings and almost innumerable princes pay allegiance, except those kings who observe the laws of Mahomet but submit to the emperor in other things."
"This map, which was in Florence, was destroyed during World War II, but the lower edge, where Ethiopia would have been shown, had already been severely mutilated so that the reproductions published before its disappearance can tell us little that is relevant to the embassy. It was signed Johannes presbyler rector sancti Marci de portu Janue me fecit. Fischer, who first published the map, accepted the identification of Johannes presbyter with Giovanni da Carignano, but contended that the embassy came from Persia and must have been responsible for some information about the western part of the Ilkhanid empire which the map provides.”