Normandy is a geographical and cultural region in Northwestern Europe, roughly coextensive with the historical Duchy of Normandy.
Normandy comprises mainland Normandy (a part of France) and the Channel Islands (mostly the British Crown Dependencies). It covers 30,627 square kilometres (11,825 sq mi). Its population is 3,499,280. The inhabitants of Normandy are known as Normans, and the region is the historic homeland of the Norman language. Large settlements include Rouen, Le Havre and Cherbourg.
The cultural region of Normandy is roughly similar to the historical Duchy of Normandy, which includes small areas now part of the departments of Mayenne and Sarthe. The Channel Islands (French: Îles Anglo-Normandes) are also historically part of Normandy; they cover 194 square kilometres (75 sq mi) and comprise two bailiwicks: Guernsey and Jersey, which are British Crown Dependencies.
Normandy's name comes from the settlement of the territory by Vikings ("Northmen") starting in the 9th century, and confirmed by treaty in the 10th century between King Charles III of France and the Viking jarl Rollo. For almost 150 years following the Norman conquest of England in 1066, Normandy and England were linked by having the same person reign as both Duke of Normandy and King of England.