'the Vast One'), came to be used to designate the Brittany Peninsula, as in Old Irish Letha, Old Welsh Litau, Old Breton Letau, or in the Latinized form Letavia.
Pliny lists the following Celtic tribes as living in the area: the Aedui and Carnuteni as having treaties with Rome; the Meldi and Secusiani as having some measure of independence; and the Boii, Senones, Aulerci (both the Eburovices and Cenomani), the Parisii, Tricasses, Andicavi, Viducasses, Bodiocasses, Veneti, Coriosvelites, Diablinti, Rhedones, Turones, and the Atseui.
Some hint of the complicated cultural web that bound Armorica and the Britanniae (the "Britains" of Pliny) is given by Caesar when he describes Diviciacus of the Suessiones as "the most powerful ruler in the whole of Gaul, who had control not only over a large area of this region but also of Britain"[8] Archaeological sites along the south coast of England, notably at Hengistbury Head, show connections with Armorica as far east as the Solent.
After the legions retreated from Britannia (407 AD) the local elite there expelled the civilian magistrates in the following year; Armorica too rebelled in the 430s and again in the 440s, throwing out the ruling officials, as the Romano-Britons had done.
[11] These settlers, whether refugees or not, made the presence felt of their coherent groups in the naming of the westernmost, Atlantic-facing provinces of Armorica, Cornouaille ("Cornwall") and Domnonea ("Devon").
[14] Vikings settled in the Cotentin peninsula and the lower Seine around Rouen in the ninth and early tenth centuries and, as these regions came to be known as Normandy, the name Armorica fell out of use in the area.
The home village of the fictional comic-book hero Asterix was located in Armorica during the Roman Republic; there, "indomitable Gauls" hold out against Rome.
The unnamed village was reported as having been discovered by archaeologists in a spoof article in the British The Independent newspaper on April Fool's Day in 1993.