Jersey is a Crown dependency of the United Kingdom, ruled by the Crown in right of Jersey, off the coast of Normandy, France. Jersey was part of the Duchy of Normandy, whose dukes went on to become kings of England from 1066. After Normandy was lost by the kings of England in the 13th century, and the ducal title surrendered to France, Jersey and the other Channel Islands remained attached to the English crown.

The flag of Jersey has unknown origins, but links with St Patrick's saltire have been suggested. Saint Patrick's Saltire or Saint Patrick's Cross is a red saltire (X-shaped cross) on a white field, used to represent the island of Ireland or Saint Patrick, the patron saint of Ireland. The flags of Alabama and of Spanish Florida are similar in style.

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