The Germanic, Italic, and Celtic languages, all branches of the Indo-European language family, have fascinated linguists for centuries. When Germanic first appeared in writing in the second century CE, it existed as a single runic script and language, closely resembling Proto-Germanic. This language was spoken around the Jutland peninsula and southward towards the Alps. Linguists estimate Proto-Germanic's emergence between 500 BCE and 2000 BCE, evolving from dialects brought by the Corded Ware warbands.
Italic languages, including Latin, Oscan, and Umbrian, had already diverged when first written. Proto-Italic is believed to have originated in Italy before 1000 BCE, based on early Italic inscriptions found there. The origins of Proto-Celtic are debated, with theories ranging from the Atlantic coast to the Austrian Alps. A prominent theory suggests the French-German borderlands due to the high concentration of Celtic place and river names.
Rivers like the Main and Meuse were named after Celtic deities, and the Neckar likely derives from the Celtic root "nik," meaning "wild water". Proto-Celtic's vocabulary lacks maritime terms, suggesting its speakers were not seafarers; linguist David Stifter notes they borrowed words for 'ship' and 'sail'. Germanic, Celtic, and Italic share common ancestry, evident in grammar, pronunciation, and core vocabulary. Recent genetic evidence supports the Italo-Celtic hypothesis, suggesting a closer relationship between Italic and Celtic languages, while discrediting the Italo-Germanic hypothesis.