Southwestern Brittonic languages

Southwestern Brittonic
Geographic distribution:	Cornwall, Brittany
Linguistic classification:	Indo-European Celtic Brittonic Southwestern Brittonic
Proto-language:	Proto-Southwestern Brittonic
Subdivisions:	Cornish Breton
Glottolog:	sout3176

The Southwestern Brittonic languages are the Brittonic Celtic tongues spoken in South West England and Brittany since the Early Middle Ages. During the period of their earliest attestation, the languages appear to be indistinguishable, but eventually they evolved into the Cornish and Breton languages. They evolved from the Common Brittonic formerly spoken across most of Britain and were thus related to the Welsh and Cumbric dialects spoken in Wales and Hen Ogledd (northern Britain), respectively.

The earliest stage of the languages, Primitive Cornish/Primitive Breton, is unattested. Written sources are extant from the Old Cornish/Breton period, roughly 800–1100, in which phase the languages are basically identical. As such, some linguists such as Peter Schrijver suggest that the terms "Old Cornish" and "Old Breton" are geographical rather than linguistic, only describing whether a text was written in Cornwall or Brittany.

Description

Some of the sound changes that distinguish Southwestern Brythonic from Welsh include:

• the raising of */(ɡ)wo-/ to /(ɡ)wu-/ in a pretonic syllable (in Welsh there was no raising)
• the fronting of */ɔː/ to /œː/ (in Welsh it diphthongized to /aw/)
• the fronting of */a/ to */e/ before */iː/ or */j/ in an old final syllable (in Welsh it diphthongized to /ei/)

Other significant differences are found in Welsh innovations in which Southwestern Brythonic did not participate, such as the development of the voiceless alveolar lateral fricative /ɬ/.