After William the Conqueror invaded and defeated the English at the Battle of Hastings, the Dutchy fell under the rule of England until 1204 when Phillip II of France conquered it. The Treaty of Paris (1295) gave the lands, with the exception of the Channel Islands back to France (with the exception of the island of Chausey). This which is why the Queen of England is toasted on the islands as the Duke of Normandy (or Our Queen, the Duke) even though according to Salic law she is not.