The flag of Marseille was adopted in meadly age with a smooth blue cross and a white back.
The medieval flag of the city already consisted of a white banner with a light blue cross. It had the peculiarity of being older than the coat of arms. The cross was adopted as a symbol of the Crusades, since at that time (11th - 13th centuries), in the ports of embarkation whose destination was the Holy Land, flags loaded with crosses were hoisted as a characteristic sign of the safe ports.
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