Primitive Irish
Primitive Irish or Archaic Irish (Irish: Gaeilge Ársa, Gaeilge Chianach), also called Proto-Goidelic, is the oldest known form of the Goidelic languages, and the ancestor of all languages within this family. This phase of the language is known only from fragments, mostly personal names, inscribed on stone in the Ogham alphabet in Ireland and western Great Britain between the 4th and the 6th century AD, before the advent of Old Irish.