Star of David on Middle Ages Charts

Star of David on a Nautical Chart of Mediterranean area from
LUÍS TEIXEIRA, PORTOLAN CHART. Lisbon, ca. 1600 

Source: Wikipedia entry: User:Geagea/gallery

JOAN MARTINES, PORTOLAN ATLAS. Italy, ca. 1578
Source:  Wikipedia Category:Star_of_David?uselang=de

Carta catalana (Mappamondo catalano) 1452 ?
Source:  Wikipedia Category:Star_of_David?uselang=de

 Evelyn Edson wrote in her book The world map, 1300-1492: the persistence of tradition and transformation that the star of david flag flying over Brisch (modern Bissa- town in North Africa) maybe refrers to the  large community of Jews in this coastel town.