Petrus Roselli, the maker of the portolan chart, was from a well-known family of mapmakers on Majorca.
It appears that Roselli was Italian–or at least his family was originally from Italy. His ancestors may have included Italian Jews who lived in Barcelona and converted to Christianity in the thirteenth century. Nicholas Roselli, a cardinal, died in Majorca in 1367. Whether Petrus Roselli was of this family is not known, but it is clear that his portolan charts were made on Majorca. Petrus Roselli was the subject of an article by Heinrich Winter in Imago Mundi. He writes: "P. Roselli may have been of Italian origin or not, but in the circumstances he must be considered a Catalan and his work the product of Catalan erudition and skill, which were well known for the production of other aids to navigation and astronomy. The contrary view [on his nationality] still needs proof" (Winter 1952, 1).
One advantage in studying Roselli is that he had a long career as a cartographer (two Young Navigators linkdecades) and six portolan charts known to have been made by him have survived, plus two additional ones are thought to be possibly his, making a total of eight. They date from 1447, 1456, 1462, 1464, 1465 and 1466. One of the two other portolan charts that are possibly attributed to Roselli is undated; the other is dated 1468.