Former duchy and province of north-western France on the Armorican peninsula, coextensive with modern French Departments of Finistére, Côte d'Armor, Morbihan, Ille-et-Vilaine, and Loire-Atlantique (although the last is officially declared not a part of Brittany since the Vichy Regime, 1941). Occupying 18,630 square miles, the region is more than twice as large as Wales and more than half the size of Ireland. Brittany has been occupied by Celtic-speaking populations since pre-Roman times, but it takes its name from the Brythonic people who fled the isle of Britain in the 5th century. In Breton it is known as Breizh (cf. Breizh Uhel, ‘east or Upper Brittany’ (Fr. Haute Bretagne); Breizh Izel, ‘west or Lower Brittany’ (Fr. Basse Bretagne); in Welsh it is Llydaw; Corn. Breten Vyghan; OIr. Letha; ModIr. An Bhriotáin; ScG Breatainn na Frainge; Manx Yn Vritaan. The coastal regions are known in Breton literature and folklore as Arvor [Bret. Ar-Mor, sea], while the interior is known as Argoad [Bret. Ar-Goat, Ar-Koad, woods, forest]. In early Christian times the region now called Brittany was divided among three petty kingdoms, Domnonia in the north, Cornouaille in the south and west, Bro Waroch in the south and east. The Fir Morca of early Irish myth, although sometimes placed in west Limerick, are Armoricans/Bretons.
In Welsh tradition the emigrants to Brittany were led by the legendary St. Cynan Meiriadog (or Meriadoc), who is described as a conqueror in Breuddwyd Macsen Wledig [The Dream of Macsen Wledig]. According to that story, the Roman emperor Macsen [Maximus] rewarded his British allies with a portion of Gaul then called Brytanieid. Macsen had married a British princess, Elen, whose brother Cynan had brought a British army to Rome. Cynan and his allies cut out the tongues of all the women of the province lest the language of the conquerors be corrupted, and thus they name it Llydaw [W lled, half; taw, silent]. Cynan is also described as the British invader in Breton legends, where he is known as Conan. With the subsequent influx of British ecclesiastics, the area increasingly became known as ‘Brittany’ instead of Armorica, although the two terms were interchangeable for many centuries.
A P-Celtic language of the Brythonic family, Breton is historically linked to both Welsh and the now extinct Cornish. On the testimony of Giraldus Cambrensis (12th cent.), spoken Breton was more closely related to the Cornish of his day than to Welsh. But despite many lexical similarities, modern spoken Breton and Welsh are not mutually comprehensible. In 1907 scholars determined that Breton language and tradition should be divided into four parts. Three in the north and west are closely interrelated: KLT, named for Kernev (Cornouaille), Leon (or Léon), and Treger (Trégor, Tréguier). The G dialect of the south-west stands somewhat apart, taking its name from Gwened, Breton for Vannes, capital of Morbihan; the dialect is also known as Vannetais in French, Gwenedeg in Breton. The first great political leader of the Bretons, subject of many legends, was Nominoë (9th cent.), who first accepted Frankish suzerainty but later revolted and restored Breton independence.