Zoroastrian notions of the fravashis reach back in time to the Indo-Aryan period and, earlier, to a primitive moment when as spirits of the deceased they continued to exercise power over human affairs in life. Ancestor-worship and the cult of the dead have ever since played a major part in religious observances throughout human history. It was not so much respect for the sprits of the departed, as their dread, that made the essential rituals of appeasement so elaborate. Those spirits had to be especially remembered at certain times, usually anniversaries, or when not exactly recalled, then at fixed times during the seasonal year during which all the spirits of the dead were ritually summoned to partake of commemorative feasts where offerings were presented solemnly in their names.
