The origins of the Etruscans are lost in prehistory. Historians have no literature, no texts of religion or philosophy; therefore much of what is known about this civilization is derived from grave goods and tomb findings. The main hypotheses are that they are indigenous, probably stemming from the Villanovan culture or from the Near East (Anatolia). Knowledge of the Etruscan language is still far from complete. The Etruscans are believed to have spoken a non-Indo-European language.