Ferdinand and Isabel
Today many Americans will celebrate Columbus Day. Columbus landed in the "New World" on October 12, 1492. The flags carried by Columbus on his first exploration have always been of great interest to the historians and vexillologists. Spanish history is much too complicated for me to understand or explain in any detail, but here’s a very short explanation of the flags that Columbus most likely took with him.
The marriage in 1469 of royal cousins, Ferdinand of Aragon (1452-1516) and Isabel of Castile (1451-1504), unified and brought stability to the two kingdoms. Isabel was Regent—the Queen—and Ferdinand was king consort. Isabel was Queen of Castile and Leon. Ferdinand was King of Aragon and Sicily, and Count of Barcelona, which was comprised his realm.
The flag shown at left was Isabel’s flag—not Ferdinand’s, nor was it the flag of "Spain" either. Queen Isabel was Regent, and it was she who financed the expedition; Columbus carried her royal standard. Isabel’s flag was the flag of Castile and Leon—and was possibly carried as a banner, with the point hanging down (and with the elements righted to that orientation).
The captain of Columbus’s three ship expedition most likely carried the flag on the left: the personal flag of "Fernando and Ysabel." It was their unique family flag.
A third flag was the Royal Standard of the Catholic Kings 1492-1506. This flag featured the arms of the Catholic Kings and Queen. Look closely and you will see the elements of her flag. The heraldry it is described thus: white with the arms of the Catholic Kings—quarterly, 1st and 4th quarters counterquartered of Castile and Leon, 2nd and 3rd quarters per pale Aragon and Sicily; crest: an open royal coronet or; supporter: St. John’s eagle displayed sable, nimbed, beaked and membered or, langued and armed gules; at dexter and sinister base of the escutcheon, respectively, a yoke and a bundle of five arrows, all proper the arrows pointed argent