The Channel Islands fall into two separate self-governing Bailiwicks. Both the Bailiwick of Guernsey and the Bailiwick of Jersey are British crown dependencies, but neither is part of the United Kingdom. They have been part of the Duchy of Normandy since the 10th century and Queen Elizabeth II is often referred to by her traditional and conventional title of Duke of Normandy. However, pursuant to the Treaty of Paris (1259) she is not the Duke in a constitutional capacity and instead governs in her right as Queen.