ProtoIndoEuropees

ProtoIndoEuropees, in linguistics typically called Proto-Indo-European (PIE), is the reconstructed common ancestor of the Indo-European language family. It is not attested in any written text; knowledge about PIE comes from the comparative method, which identifies systematic sound correspondences and shared basic vocabulary across its descendant languages.

Most scholars place PIE speakers in the late Neolithic or early Bronze Age, with the homeland commonly identified as the Pontic–Caspian steppe (the Kurgan hypothesis) and alternative proposals such as the Anatolian hypothesis. Dating estimates for PIE generally fall around 4500–2500 BCE, though exact dates vary among researchers.

Linguistically, PIE is reconstructed as a highly inflected language. It had three genders, three numbers (singular, dual, plural), and an extensive case system (nominative, accusative, genitive, dative, instrumental, locative, ablative, vocative, among others). Verbs exhibited complex morphology for tense, aspect, mood, and voice, with suffixal derivation and thematic vowels. A notable feature is the presence of laryngeal consonants (h1, h2, h3) whose effects are still detectable in many descendant languages and were later integrated into the phonological system.

A traditional division highlights Centum versus Satem branches, reflecting different historical sound changes and early divergence within Indo-European. From PIE descend most major branches, including Indo-Iranian, Greek, Italic, Celtic, Germanic, Baltic, and Slavic, with Anatolian and Tocharian representing earlier-extinct lineages.

ProtoIndoEuropees remains central to historical linguistics as the theoretical scaffolding for understanding how a single ancestral language evolved into a wide family of languages across Eurasia.