Blurb:

The cult of Cybele and Attis was an ancient cult disseminated throughout the entire Roman Empire. Among the rites held by its followers, there were the so-called Day of Blood (dies sanguinis) which, according to the Calendar (or Chronography) of Philocalus (354 CE), was celebrated on 24 March. On this day the worshipers and priests (galli) of Cybele/Attis flagellated themselves until they bled profusely, and with their blood they sprinkled Cybele’s effigy as well as the altars of the temple, while the initiates castrated themselves and offered their testes to the goddess as a real-life imitation of what happened mythologically to the goddess’ consort Attis. The present contribution offers a preliminary systemization of this glaringly maladaptive and quite puzzling belief-behaviour complex in the anthropological and neurocognitive frame of the so-called extreme rituals, highlighting the specific in-group benefit reaped by worshipers and initiates (e.g., community cohesion through costly signalling and credibilityenhancing displays).