Old Irish is the name given to the oldest form of the Irish language, or, rather, the Goidelic languages, for which extensive written texts are possessed. It was used from the 6th to the 10th centuries, when it gave way to Middle Irish.A still older form of Irish is known as Primitive Irish. Fragments of Primitive Irish, mainly personal names, are known from inscriptions on stone written in the Ogham alphabet. These inscriptions date from about the 4th to the 6th centuries. Primitive Irish is still very close to Common Celtic, the ancestor of all Celtic languages.
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