Aethicus Ister (Aethicus of Istria) was the protagonist of the 7th/8th-century Cosmographia written by a man of church Hieronymus.
André Vernet, who edited Bernard's Cosmographia, believed that he lived from 1085 to 1178; the only certain date in his life is 1147, when the Cosmographia was supposedly presented to Pope Eugene III.
The woodcut “Rhinoceros”, for the work Cosmographia (or “Cosmography”) by Sebastian Munster is, along with his maps, also very famous and depicts a rhinoceros truly based on the Dürer sketch.
Among his numerous published works was an 1854 edition of Aethicus Ister titled Aethici Istrici Cosmographia ab Hieronymo ex Graeco Latinum breviarium redacta.