The Vedic beliefs and practices of the pre-classical era were closely related to the hypothesised Proto-Indo-European religion, and show relations with rituals from the Andronovo culture, from which the Indo-Aryan people descended. The Indo-Aryans were speakers of a branch of the Indo-European language family, which originated in the Sintashta culture and further developed into the Andronovo culture, which in turn developed out of the Kurgan culture of the Central Asian steppes. The Vedic religion was the religion of some of the Vedic Indo-Aryan tribes, the aryas, who migrated into the Indus River valley region of the Indian subcontinent. Although the word is only attested in Indo-Iranian traditions, Manfred Mayrhofer has proposed a Proto-Indo-European origin from the root * sew(h). *sau-ma- is the drink prepared by pressing the stalks of a plant, but the word and the related practices were borrowed by the Indo-Aryans from the Bactria–Margiana culture (BMAC). According to Geldner (1951), the word is derived from Indo-Iranian roots *sav- (Sanskrit sav-/su) 'to press', i.e. Soma is a Vedic Sanskrit word that literally means 'distill, extract, sprinkle', often connected in the context of rituals. Non-Indian researchers have proposed candidates including the fly agaric, Amanita muscaria Psilocybin mushrooms, Psilocybe cubensis wild or Syrian rue, Peganum harmala and ma huang, Ephedra sinica. Traditional Indian accounts, such as those from practitioners of Ayurveda, Siddha medicine, and Somayajna called Somayajis, identify the plant as 'Somalata' ( Sarcostemma acidum).

There has been much speculation about the most likely identity of the original plant.

Both in the ancient religions of Historical Vedic religion and Zoroastrianism, the name of the drink and the plant are not exactly the same. The texts describe the preparation of soma by means of extracting the juice from a plant, the identity of which is now unknown and debated among scholars. The Rigveda mentions it, particularly in the Soma Mandala. In the Vedic tradition, sóma ( Devanagari: सोम) is a ritual drink of importance among the early Vedic Indo-Aryans.

Soma gordon wasson