Fetiales

A fetial (Latin plural fetiales) was a type of priest in Ancient Rome. They formed a collegium devoted to Jupiter as the patron of good faith.

The duties of the fetials included advising the senate on foreign affairs and international treaties, making formal proclamations of peace and of war, and confirming treaties. They also carried out the functions of traveling heralds or ambassadors (Pater Patratus).

The first mention of the fetials by Livy occurs in the context of the war between Alba Longa and Rome, during which the Roman king Tullus Hostilius appointed M. Valerius as a fetial and Sp. Fusius as pater patratus, for the purpose of binding Rome and Alba Longa by a treaty.

According to Livy, the ritual by which the fetials were to declare war, the ritual of rerum repetitio, was introduced to Rome by Ancus Marcius, borrowing on the traditions of the Aequicolae. However he had already described the ritual actions of the fetials when recording the wars of Tullus Hostilius. Thus some scholars think the mentions of the Aequi may be a misinterpretation due to a folk etymology connecting Aequi to aequus, the Latin adjective for fair. On the other hand ancient sources support the tradition that the priesthood was created under the influence of Aequian king Ferter Resus.

The ritual of rerum repetitio, a request of restitution or reparations, involved the pater patratus. Wearing a woolen hair-band, he was to announce Roman demands using a series of prescribed phrases, first at the enemy's frontier, then when he passes over the borders, again to the first man he meets, again on entering the enemy's gate, and again on entering the forum at the presence of local magistrates. If the demands are not met, the pater patratus declares war within 33 days and returns to Rome to await the resolution of the Roman king and senate. Once they have resolved to go to war, a fetial returns to the enemy frontier carrying a javelin with a steel or burnt tip, and dipped in blood. He declares war on the enemy, and throws the javelin into their territory.

The fetial is connected to matters of law and not directly to war, hence in his formulae he never invokes Mars, but Jupiter, Juno (or perhaps Janus) and Quirinius.

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