When Christopher Columbus reached the New World on October 12, 1492 one of the flags he displayed was the Flag of Castile and León. He also displayed the flags of his ships' captains and this expeditionary banner.

The original documents of Columbus' expedition describe a banner, white with a green cross and the crowned initials F and Y, which stood for Fernando and Ysabel, the Catholic Monarchs. It is known that it was a Captain's Ensign ("La Capitana"). It was used to distinguish the ships under Columbus' command. It was not a personal, private flag belonging to him, but a sign of the fleet under his authority. The symbols the flag contains (the crowned F and the crowned Y separated by a cross) are engraved in what is claimed to be Columbus' burial mound in the Cathedral of Seville, but no flag shape is described.