There are three island territories within the British Isles that are known as Crown Dependencies; these are the Bailiwicks of Jersey and Guernsey which make up Channel Islands, and the Isle of Man. The Crown Dependencies are not part of the United Kingdom, but are self-governing possessions of the British Crown. The three Crown Dependencies have their own varying forms of self-administration, although the United Kingdom government is responsible for certain areas of policy such as defence and foreign affairs. The King’s special relationship with the Crown Dependencies is reflected by the titles he has in them.

The Channel Islands were part of the Duchy of Normandy when Duke William, following his conquest of England in 1066, became William I. In 1106, William’s youngest son Henry I seized the Duchy of Normandy from his brother Robert; since that time, the English and subsequently British Sovereign has held the title Duke of Normandy. By 1205, England had lost most of its French lands, including Normandy. However, the Channel Islands, part of the lost Duchy, remained a self-governing possession of the English Crown.