England’s flag is represented by a red cross set on a white background. This cross is known as the St George’s Cross and has represented England is various forms from as far back as the Middle Ages and the Crusades (a religiously sanctioned series of military campaigns, which were waged by a large proportion of Western Europe in their efforts to restore Christianity and reclaim Christian ownership of modern-day Israel). Because of its use since the 16th century, it has come to be one of the most prominent and well-known symbols of England. The red cross was also an emblem of a knighthood system originating to England’s medieval times, known as the Most Noble Order of the Garter. With such global recognition and acclaim, it was an obvious emblem for the official flag of the country.
The Pope had decided that all English Crusaders should wear red tunics with white crosses, while the French opted for red on white. The English then wanted to reclaim their emblem of a red cross on a white tunic and, in 1188, the kings of each country decided to exchange their flags. However, some of the French soldiers continued to wear their old tunics, resembling the English. For this reason, the red cross on the white background eventually became the symbol for the Crusaders, irrespective of their nationality.
During the Battle of Evesham in 1265, the English royalists wore a red cross on a white uniform to identify themselves as being separate from the rebel barons that had worn white crosses during the Battle of Lewes just some months before. Ten years later, the St George’s Cross was used as England’s identifying emblem during the Welsh War.
Some historians believe that the St George’s Cross was adopted from Genoa’s flag in 1190 for use on English sailing vessels that were going into the Mediterranean and Black seas so that the Genoese fleets would protect them.
The flag of the United Kingdom (also known as the Union Jack) has incorporated the St George’s Cross from the English flag to a major degree. The St Patrick’s Cross (a red “x” on a white background) has also been used to indicate the merger of the Kingdom of Great Britain with the Kingdom of Ireland. This flag continues to be used to represent the United Kingdom, despite the fact that only Northern Ireland remains a member of the union.