High Quality Content by WIKIPEDIA articles! The Proto-Indo-European language (PIE) is the unattested, reconstructed common ancestor of the Indo-European languages, spoken by the Proto-Indo-Europeans. The existence of such a language has been accepted by linguists for over a century, and there have been many attempts at reconstruction. Nevertheless, many disagreements and uncertainties remain.There are several competing hypotheses about when and where PIE was spoken. The Kurgan hypothesis is "the single most popular" model, postulating that the Kurgan culture of the Pontic steppe were the hypothesized speakers of the reconstructed Proto-Indo-European language. However, alternative theories such as the Anatolian urheimat and Armenian hypothesis have also gained acceptance.