Flag of Free France
The flag of Free France, shown above, contains the Cross of Lorraine, also known as the Cross of Anjou. Why Lorraine? Because - as with Joan of Arc - it symbolized the lost provinces of France, on this occasion lost to Germany after 1871. It was the only official flag that Free France used before becoming the Government of the French Republic in 1944. Below is the naval version:
The Cross had enormous symbolic significance for French resistance to the Nazis. Here it is at Courseulles-sur-Mer, Calvados, Normandy, where De Gaulle landed on 14 June 1944.