The coat of arms of the Duke of Cornwall is a Crusader shield on which are displayed 15 golden bezants (gold coins) in the shape of a triangle with the motto "One and All"
The story of the 15 bezants occurs during the Crusades when the Duke of Cornwall was captured by the Saracens. A ransom of 15 bezants (bezants being gold coins named after Byzantium) was demanded. The people of Cornwall to raised the money for the ransom. It was paid and the Duke was set free. The inhabitants had all helped together One and All to raise the money – hence the motto.
However it is difficult to verify this as Richard joined the Sixth Crusade and went to the Holy Land. He fought in no battles but managed to negotiate for the release of prisoners and the burials of Crusaders killed at a battle in Gaza in 1239. He also refortified Ascalon, which had been demolished by Saladin.
The golden bezants on sable were apparently already present as border of the shield of Richard, made Count of Cornwall by his brother Henry III of England in 1227.
The arms might be dated 1337, when Edward 'the Black Prince', son of king of England Edward III, was made Duke of Cornwall.
Edward IV (April 28, 1442 – April 9, 1483) roll dated around 1461 shows a banner for the Duchy of Cornwall
This shows the 15 bezants, but in a different shape
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