The map’s representation of the world’s southernmost regions and many of the cartouches regarding Africa, Persia, and the Indian Ocean basin, reflect the Islamic legacy of geographical knowledge. Islamic sources, for example, maintained that the outer borders of the navigable seas were marked by a circular chain of islands, beyond which lay an immense, impenetrably dark ocean. This was a view expressed by al-Idrisi (1099/100-1166), a geographer in the court in Palermo of the 12^th-century Norman King Roger II (1095-1154).

Also of Arabic origin are many place names adopted by Fra Mauro (active ca. 1430-ca. 1459/1464): Mahal and Duiamoal, Indian Ocean islands that probably correspond to the Maldives, with “mahal” meaning “islands”; Isola Chancibar, Zanzibar, whose root “Zanj” means “land of the black men”; Abassia in Africa, a variation of “Habash”, the name given to Ethiopian lands; Ifat, also in Ethiopia, derived from the 13^th-century Sultanate of Yifat; Macin, indicating the regions between India and China, a variant on the Arabic form “Madjin”, which in turn may derive from the Sanskrit “Mahacin”, meaning Greater China; and, to return to Africa, Dolcarmin, derived from “Dhu ‘l Karneim”, or “two-horned man”, a place name based on a Arabic epithet referring to Alexander the Great (356-323 BCE).

Fra Mauro did not speak Arabic, but as a late medieval Christian cartographer his worldview was permeated by Islamic culture. Venice, in particular, had strong connections with the Muslim world. Many Venetians lived in Cairo, Alexandria, and the Mediterranean Islamic ports. Many Venetians spoke Arabic and Persian, among them Marco Polo (1254-ca. 1324), whose knowledge of Persian, an official language of the Mongol court, led to his service for Kublai Khan (1215-1294). The Venetian presence in far eastern and middle eastern markets favored the diffusion of Islamic culture, to which Fra Mauro’s map is greatly indebted.