Brittany (; ; , or ; Gallo: Bertaèyn ) is a peninsula, historical country and cultural area in the west of modern France, covering the western part of what was known as Armorica during the period of Roman occupation. It became an independent kingdom and then a duchy before being united with the Kingdom of France in 1532 as a province governed as a separate nation under the crown. Brittany has also been referred to as Little Britain (as opposed to Great Britain, with which it shares an etymology). It is bordered by the English Channel to the north, Normandy to the northeast, eastern Pays de la Loire to the southeast, the Bay of Biscay to the south, and the Celtic Sea and the Atlantic Ocean to the west. Its land area is 34,023 km2 . Brittany is the site of some of the world's oldest standing architecture, home to the Cairn of Barnenez, the Tumulus Saint-Michel and others, which date to the early 5th millennium BC. Today, the historical province of Brittany is split among five French departments: Finistère in the west, Côtes-d'Armor in the north, Ille-et-Vilaine in the northeast, Morbihan in the south and Loire-Atlantique in the southeast. Loire-Atlantique now belongs to the Pays de la Loire region while the other four departments make up the Brittany region. At the 2010 census, the population of historic Brittany was estimated to be 4,475,295. In 2017, the largest metropolitan areas were Nantes (934,165 inhabitants), Rennes (733,320 inhabitants), and Brest (321,364 inhabitants). Brittany is the traditional homeland of the Breton people and is one of the six Celtic nations, retaining a distinct cultural identity that reflects its history. A nationalist movement seeks greater autonomy within the French Republic, or independence from it. Etymology The word Brittany, along with its French, Breton and Gallo equivalents Bretagne, Breizh and Bertaèyn, derive from the Latin Britannia, which means "land of the Britons". This word had been used by the Romans since the 1st century to refer to Great Britain, and more specifically the Roman province of Britain. This word derives from a Greek word, Πρεττανικη (Prettanike) or Βρεττανίαι (Brettaniai), used by Pytheas, an explorer from Massalia who visited the British Isles around 320 BC. The Greek word itself comes from the common Brythonic ethnonym reconstructed as *Pritanī, itself from Proto-Celtic *kʷritanoi (ultimately from Proto-Indo-European *kʷer- 'to cut, make'). The Romans called Brittany Armorica. It