This papers aims to evaluate the sound changes that took place between the Proto-Indo-European stage and the Proto-Celtic stage, that is to say before this proto-language started to be divided into...Show moreThis papers aims to evaluate the sound changes that took place between the Proto-Indo-European stage and the Proto-Celtic stage, that is to say before this proto-language started to be divided into several dialects giving birth to Old Irish, Old Welsh, Old Breton, Old Cornish, Gaulish, Celtiberian, and Lepontic, and to propose a relative chronologic order of those changes.Show less