Crosses in heraldry

The cross is a basic design used from pre-historic times. Its use was enormously expanded in the form of the Roman instrument of torture later known as the Christian cross from the 1st century AD with the development of Christianity. From the 11th century, and increasingly during the age of the Crusades, a variety of forms of cross symbols were developed for the purpose of the emerging system of heraldry, which appeared in western Europe in about 1200.

The cross was displayed on banners and flags from the medieval period and became common in modern times on numerous national flags.

Heraldry emerged in western Europe at the start of the 13th century out of earlier traditions. The Christian cross is one of the earliest and most widespread heraldic charges, dating back to the field signs used in the First Crusade, and used to distinguish the various noble crusaders from at least the Second Crusade. Some pre-Christian usages appear in heraldry, such as the Fylfot.

In 1188, Kings Henry II of England and Philip II of France agreed to launch the Third Crusade together, and that Henry would use a white cross and Philip a red cross. The red-on-white cross came to be used by the Knights Templar, and the white-on-red one by the Knights Hospitaller (also white-on-black); the Teutonic Order used a black-on white version.

The basic variants of the red-on-white (termed the Cross of Saint George) and the white-on-red crusaders' cross were continued independently in the flags of various states in the 13th and 14th century, including the Duchy of Genoa, the Electorate of Trier, the Bishopric of Constance and the Kingdoms of England and Georgia, which last two had special devotions to St George. on one hand; and Savoy, the war flag of the Holy Roman Empire and (possibly from the latter) Switzerland and Denmark on the other.

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