The map itself is undated, but there are clues it was created in 1491: It quotes a book published that year, and Christopher Columbus may have consulted the map (or a copy) before his great voyage.

In 1492, Christopher Columbus set sail on one of the most consequential expeditions in history. He and his crew spent more ...

Christopher ... Columbus made his way to Spain, where he gained support from the Spanish monarchy. He persuaded King Ferdinand II and Queen Isabella I to sponsor his quest to find a westward route ...