Lepontic

Lepontic was a speech-form spoken in Northern Italy around the time of Christ, attested by a handful of short inscriptions in a form of the Etruscan alphabet. It is ultimately derived from Proto-Indo-European, though its more precise family affilations are uncertain - it is sometimes regarded as Celtic, being perhaps a dialect of Gaulish, or a language in its own right, belonging to Continental Celtic or Gallo-Brittonic; while elsewhere it is viewed as connected to Italic, but with Celtic influence. So little of it survives that a clear judgement is hard to make.

The Carcegna Vase inscription

metelui.maesilalui.uenia.metelikna.asmina.krasanikna

"For Metelos Maesilalos, Venia Metelikna (and) Asmina Krasanikna (give this)."

This inscription shows o-stem masculine dative singulars in -ui (cf. Old Latin -oi, Gaulish -ui, -u), and a-stem nominative singulars in -a, as well as a patronymic/matronymic suffix -kna derived from PIE *gen- "to give birth" (cf. Lat -genus, CC -knos).

The Ornavasso Vase inscription

latumarui.sapsutai.pe.uinom.nasom

"For Latumaros and Sapsuta, Naxian wine."

Here we additionally see an a-stem dative singular in -ai, o-stem neuter nom. or acc. neuter singulars, and the words for "and" and "wine", corresponding to Lat. -que, Celtiberian -cue; and Lat. vinum respectively. This shows a change of PIE *kw > p in Lepontic; the same change occurs in Gaulish and Brittonic within Celtic, and Osco-Umbrian in Italic.