Saint George's Cross, also called Cross of Saint George, is a red cross on a white background.
Sometimes associated with Saint George, the military saint, often depicted as a crusader from the late Middle Ages, the cross has appeared on many flags, emblems, standards, and coats of arms.
Its first documented use was as the ensign of the Republic of Genoa, whereafter it was used successively by crusaders.
The symbol has since been adopted by the Swabian League in the pre-Reformation Holy Roman Empire, and it was introduced as the emblem of several countries and cities which have or had Saint George as a patron saint, notably the Republic of Genoa, the Duchy of Milan, England, Wales, and the Georgia in the Caucasus, Eastern Europe.
The cross is also found, for various reasons, on the provincial flags of Huesca, Zaragoza, and Teruel (the three provinces of Aragón in Spain) and Barcelona. It is used extensively across Northern Italy and is the symbol of Bologna, Padua, Genoa, Reggio Emilia, Mantua, Vercelli, Alessandria, and most notably of Milan, where it is often called the "Cross of Saint Ambrose". In Northern Ireland the cross appears on the flag of the loyalist paramilitary group the Ulster Volunteer Force.