Devotio

In ancient Roman religion, the devotio was an extreme form of votum in which a Roman general vowed to sacrifice his own life in battle along with the enemy to chthonic gods in exchange for a victory. The most extended description of the ritual is given by the Augustan historian Livy, regarding the self-sacrifice of Decius Mus. The English word "" derives from the Latin.

Devotio may be a form of consecratio, a ritual by means of which something was consecrated to the gods. The devotio has sometimes been interpreted in light of human sacrifice in ancient Rome, and Walter Burkert saw it as a form of scapegoat or pharmakos ritual. By the 1st century BC, devotio could mean more generally "any prayer or ritual that consigned some person or thing to the gods of the underworld for destruction."

Livy preserves the prayer formula used for making a devotio. Although Livy was writing at a time when the religious innovations of Augustus were often cloaked in old-fashioned piety and appeals to tradition, archaic aspects of the prayer suggest that it is not an invention, but represents a traditional formulary as might be preserved in the official pontifical books. The attending pontifex even dictates the wording. The syntax is repetitive and disjointed, unlike prayers given literary dress during this period in the poetry of Ovid and others. The deities invoked — among them the Archaic Triad of Jupiter, Mars, and Quirinus — belong to the earliest religious traditions of Rome. Livy even explains that he will record the archaic ritual of devotio at length because "the memory of every human and religious custom has withered from a preference for everything novel and foreign."

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