Since heraldry flourished, it needed to become regulated. It was necessary to have a language that not only accurately described the arms, but one that others could understand. The language used was Norman French. It is still being used to this day. Dukes A duke is the highest non-royal title in British peerage.
Dukes are technically princes since they descended directly from a King.
A duke is addressed as His Grace. The younger sons are addressed by the title Lord and then their Christian name. Daughters are titled Lady. The eldest sons of dukes have precedence immediately below marquesses and use one of their father's secondary titles. The Duke of Norfolk is Premier Duke of England and is also Earl Marshall.