Proto-Indo-European mythology

Proto-Indo-European mythology is the body of myths and deities associated with the Proto-Indo-Europeans. Although the mythological motifs are not directly attested – since Proto-Indo-European speakers lived in preliterate societies – scholars of comparative mythology have reconstructed details from inherited similarities in mythological concepts found in Indo-European languages, based on the assumption that parts of the Proto-Indo-Europeans' original belief systems survived in the daughter traditions.

Source: Wikipedia — Proto-Indo-European mythology (CC BY-SA 4.0)