Proto-Indo-European homeland

The Proto-Indo-European homeland was the prehistoric homeland of the Proto-Indo-European language (PIE), the region where the proto-language was spoken before it split into the dialects from which the earliest Indo-European languages later evolved with the Indo-European migrations. The Steppe theory, the Anatolian model, and the Near Eastern (or Armenian) model are the three main solutions for the Indo-European homeland, of which the Steppe theory is the most widely accepted proposal.

The search for the homeland of the Indo-Europeans began during the late 18th century with the discovery of the Indo-European language family. The methods used to establish the homeland have been drawn from the disciplines of historical linguistics, archaeology, physical anthropology and, more recently, human population genetics. The Steppe theory puts the archaic, early, and late PIE homeland in the Pontic–Caspian steppe between 4000–3000 BCE. with Lazaridis and Anthony proposing that archaic PIE ('Indo-Anatolian') emerged in an area between the Caucasus and the lower Volga (a region centered on the southwestern steppe just north of the Caucasus) c. 4400–4000 BCE.

A second possibility is the Anatolian hypothesis, which puts it in Anatolia c. 8000 BCE, but is incompatible with the genetic and linguistic data and has been "largely abandoned". A third group of proposals suggest an archaic PIE-homeland south of the Caucasus. This includes the Armenian hypothesis, which situates the homeland for archaic PIE ('Indo-Hittite') south of the Caucasus mountains, This hypothesis has gained renewed attention during the 2010s and 2020s due to aDNA research, which has resulted in various proposals for an archaic 'Indo-Anatolian' or 'Indo-Hittite' homeland south of the Caucasus or even in Iran, with Lazaridis and Anthony eventually proposing PIE emerged in an area between the Caucasus and the lower Volga.

Several other explanations have been proposed, including eastern Caspian origins, the outdated but historically prominent North European hypothesis, the Neolithic creolisation hypothesis, the Paleolithic continuity paradigm, the Arctic theory, and the "indigenous Aryans" (or "out of India") hypothesis. These are not widely accepted, and are considered to be fringe theories.