Southwestern Brythonic is one of two dialects into which the Brythonic language split following the Battle of Deorham in 577 CE; the other being Western Brythonic, which later evolved into Welsh and Cumbric. It is believed to be the common ancestor of Cornish and Breton. It has recently been the subject of a minor revival in Devon following the self-publication of a booklet entitled A Handbook of West Country Brythonic: The Forgotten Celtic Tongue of South West England C.700 A.D. (Old Devonian) by Joseph Biddulph, though the merits of Biddulph's attempted reconstruction of the language are strongly disputed by Celtic linguists (see this article's discussion page). Celtic languages are the languages spoken by the ancient Celts and their modern descendants, the Gaels, Welsh, Cornish and Bretons. ... Proto-Celtic language, also called Common Celtic, is the putative ancestor of all the known Celtic languages. ... The Continental Celtic languages are those Celtic languages that are neither Goidelic nor Brythonic. ... The Celtiberians dwelt in the Iberian Peninsula and spoke a Celtic language. ... Gaulish is the name given to the Celtic language that was spoken in Gaule before the Romans invaded. ... Lepontic is an extinct Celtic language that was once spoken in Northern Italy between 700 BCE and 400 BCE. The language is only known from a few inscriptions discovered that were written in a variety of the Northern Italic alphabet, which was related to the Old Italic alphabet. ... Galatian is an extinct Celtic language once spoken in Galatia in Asia Minor (modern Turkey) up to the fourth century. ... The Insular Celtic language hypothesis groups the Goidelic languages, which include Irish, Manx, and Scottish Gaelic, together with the Brythonic languages, of which the modern ones are Breton, Cornish and Welsh. ... The Goidelic languages are one of two major divisions of modern-day Celtic languages (the other being the Brythonic languages). ... Proto-Irish (or Primitive Irish) is the oldest known form of the Irish language, known only from fragments, mostly personal names, inscribed on stone in the Ogham alphabet in Ireland and western Britain up to about the 4th century. ... Old Irish is the name given to the oldest form of the Irish language which can be more or less fully reconstructed from extant sources. ... Irish (Gaeilge in Irish) is a Goidelic language spoken in Ireland and constitutionally recognised as the first official language of the Republic of Ireland. ... Scottish Gaelic, Scots Gaelic, or just Gaelic (Gàidhlig; IPA: ), is a member of the Goidelic branch of Celtic languages. ... The Brythonic languages (or Brittonic languages) form one of the two branches of the Insular Celtic language family. ... Welsh redirects here, and this article describes the Welsh language. ... Evolution and Extinction Cumbric was the Brythonic Celtic language spoken in much of Cumbria, Northern Northumbria, and parts of lowland Scotland until about the 11th century. ... Breton (Brezhoneg) is a Celtic language spoken by some of the inhabitants of Brittany in France. ... The Cornish language (in Cornish: Kernowek, Kernewek, Curnoack) is one of the Brythonic group of Celtic languages that includes Welsh, Breton, the extinct Cumbric and perhaps the hypothetical Ivernic. ... The Brythonic languages (or Brittonic languages) form one of the two branches of the Insular Celtic language family. ... The Battle of Deorham occurred in 577 between the West Saxons and the Celts. ... Welsh redirects here, and this article describes the Welsh language. ... Evolution and Extinction Cumbric was the Brythonic Celtic language spoken in much of Cumbria, Northern Northumbria, and parts of lowland Scotland until about the 11th century. ... The Cornish language (in Cornish: Kernowek, Kernewek, Curnoack) is one of the Brythonic group of Celtic languages that includes Welsh, Breton, the extinct Cumbric and perhaps the hypothetical Ivernic. ... Breton (Brezhoneg) is a Celtic language spoken by some of the inhabitants of Brittany in France. ... Devon is a county in South West England, bordering on Cornwall to the west, Dorset and Somerset to the east. ...

See also Devonian language.