Mourning rituals are one of the oldest rituals in history.Rituals play a large part in the continuation of community traditions. A look at the history and origins of these rituals suggests that public and formalized mourning rituals originated throughout the ancient world from the regeneration and resurrection myths and lasted for centuries. What makes the historical and genealogical study of these rituals remarkable in Iran is the amazing survival and durability of these rituals in Iran to date. The most important mourning ritual in pre-historic Iran is “Mourning Rite for Siavash”. The present study seeks to find out the mythical, historical, and ideological infrastructures of these pre-Islamic mourning rituals. The results of this historical-analytical study indicate that the main form of mourning rituals in pre-Islamic Iran, is strongly suspected to be a remnant of the very old rites of agricultural societies, which over time and under the influence of historical factors and necessities, manifested in the story of the epic martyrdom and resurrection of Siavash And has survived as part of the Siavashi rituals in ancient Iran.The results of this historical-analytical study indicate that the main form of mourning rituals in pre-Islamic Iran, is strongly suspected to be a remnant of the very old rites of agricultural societies, which over time and under the influence of historical factors and necessities, manifested in the story of the epic martyrdom and resurrection of Siavash And has survived as part of the Siavashi rituals in ancient Iran.