Instituted by King Ferdinand of Spain in the late 15th Century, this Standard was not the Imperial Colors used to identify Spain. More of a personal flag of “announcement”, King Ferdinand used this Standard to identify his Kingdoms of Castile and Aragon (as well as Sicily). Possibly flown to show his and his Queen's presence in Court, the flag consisted of 4 Cantons (Quadrants). The upper left and bottom right Cantons were red and and featured a gold Castle. The upper right and lower left Cantons were white and featured a red Imperial Lion. This flag was indicative to King Ferdinand's reign only.