History of the Welsh language

The history of the Welsh language spans over 1400 years, encompassing the stages of the language known as Primitive Welsh, Old Welsh, Middle Welsh, and Modern Welsh.

Welsh evolved from British, the Celtic language spoken by the ancient Britons. Alternatively classified as Insular Celtic or P-Celtic, it probably arrived in Britain during the Bronze Age or Iron Age and was probably spoken throughout the island south of the Firth of Forth. During the Early Middle Ages the British language began to fragment due to increased dialect differentiation, evolving into Welsh and the other Brythonic languages (Breton, Cornish, and the extinct Cumbric). It is not clear when Welsh became distinct.

Kenneth H. Jackson suggested that the evolution in syllabic structure and sound pattern was complete by around 550, and labeled the period between then and about 800 "Primitive Welsh". This Primitive Welsh may have been spoken in both Wales and the Hen Ogledd ("Old North"), the Brythonic-speaking areas of what is now northern England and southern Scotland, and therefore been the ancestor of Cumbric as well as Welsh. Jackson, however, believed that the two varieties were already distinct by that time. The earliest Welsh poetry – that attributed to the Cynfeirdd or "Early Poets" – is generally considered to date to the Primitive Welsh period. However, much of this poetry was supposedly composed in the Hen Ogledd, raising further questions about the dating of the material and language in which it was originally composed.

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