Riothamus (also spelled Riotimus, Rigothamus, Rigotamos), was a military leader and considered "King of the Brittones" (c.470). Because the name means "highest leader", some scholars have suggested it may be a title, and not a personal name. It has usually been assumed that the "Brittones" or "Brittani" refers to the Bretons or the people of Brittany, a British colony in Armorica in northern Gaul, but the reference by Jordanes in his The origin and deeds of the Goths which states that they "came ... by way of the Ocean" could mean that he was a leader in mainland Britain or even the leader of the British people on both sides of the English Channel. Events Euric, king of the Visigoths, defeats an attempted invasion of Gaul by the Celtic magnate Riothamus. ... Breton can refer to: The Breton language A person from Brittany Author André Breton This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... Traditional coat of arms This article is about the historical duchy and French province, as well as the cultural area of Brittany. ... Armorica or Aremorica is the name given in ancient times to the part of Gaul that includes the Brittany peninsula and the territory between the Seine and Loire rivers inland to an indeterminate point. ... Gallia (in English Gaul) is the Latin name for the region of western Europe occupied by present-day France, Belgium, western Switzerland and the parts of the Netherlands and Germany on the west bank of the Rhine river. ... The Origin and Deeds of the Goths (Latin: De origine actibusque Getarum), commonly referred to as Getica, was written by Jordanes, probably in Constantinople, and was published in AD 551. ... The English Channel ( French:La Manche) is the part of the Atlantic Ocean that separates the island of Great Britain from northern France, and joins the North Sea to the Atlantic Ocean. ...

He took part in the Western Roman Emperor Anthemius' campaign against Euric, king of the Visigoths. Euric defeated his attack, and Riothamus vanishes from history while retreating towards a small town in Burgundy called Avallon. A letter to Riothamus from Sidonius Apollinaris, who requested support to act against troublemaking Bretons, has survived. The Western Roman Empire is the name given to the western half of the Roman Empire after its division by Diocletian. ... Procopius Anthemius (c. ... Euric, also known as Eurico or Erwig (c. ... The Visigoths, originally Tervingi, or Vesi (the noble ones), one of the two main branches of the Goths (of which the Ostrogothi were the other), were one of the loosely-termed Germanic peoples that disturbed the late Roman Empire. ... Coat of arms of the 2nd duchy of Burgundy and later of the French province of Burgundy Burgundy ( French: Bourgogne) is a historic region of France, inhabited in turn by Pre-Indo-European people, Celts ( Gauls), Romans ( Gallo-Romans), and various Germanic peoples, most importantly the Burgundians and the Franks. ... Gaius Sollius Modestus Sidonius Apollinaris (ca 430 - after 489), poet, diplomat, bishop, is the single most important surviving author from fifth-century Gaul according to Eric Goldberg (see link). ...

Riothamus has been identified as a source for the historical King Arthur by some recent scholars (notably Geoffrey Ashe and Leon Fleuriot). In any case, Riothamus' activities in Gaul may be the seed from whence grew the tradition (first recorded by Geoffrey of Monmouth in his Historia Regum Britanniae) that Arthur crossed the English Channel from Britain and attacked Rome. The existence of King Arthur continues to be hotly debated among medieval historians. ... Geoffrey of Monmouth was a clergyman and one of the major figures in the development of British history. ... Geoffrey of Monmouths Historia Regum Britanniæ (English: The History of the Kings of Britain) was written around 1136. ... Location within Italy The Roman Colosseum Rome (Italian and Latin: Roma) is the capital city of Italy and of its Latium region. ...