It has been debated for decades whether the Italic and Celtic language families could descend from a single common ancestor, usually called Italo-Celtic. Since laryngeal developments are amongst...Show moreIt has been debated for decades whether the Italic and Celtic language families could descend from a single common ancestor, usually called Italo-Celtic. Since laryngeal developments are amongst the earliest phonological developments in both Italic and Celtic, they could shed more light on the evolution of these branches shortly after Proto-Indo-European started disintegrating, and in particular on the possibility of a shared Italo-Celtic stage. This thesis analyzes Celtic and Italic laryngeal developments in three specific environments that have often been connected to the Italo-Celtic question: laryngeals after vowels in pretonic syllables (Dybo’s Law), laryngeals between consonants in word internal syllables, and laryngeals in CRHC clusters. On the basis of these, it is concluded that laryngeal developments offer some possible shared Italo-Celtic developments, and no strong arguments against an Italo-Celtic linguistic unity. The final chapter of the thesis proposes a chronology of laryngeal related sound changes that could explain both the similarities and the divergences between Italic and Celtic.Show less