NETTUNO and NEPTUNALIA. - Neptunus, an ancient Roman divinity, already appears, together with his festival, the Neptunalia (23 July), in the oldest Roman Calendar.
Literary evidence identifies him with the Greek Poseidon, classically conceived as god of the sea; this character, however, is improbable in a god of that ancient Rome which had no access to the sea. Since all the documentation is under the influence of that identification, and since the name of Nettuno has hitherto not been etymologically explained, it is difficult to reconstruct the original figure of the god. The cultic facts that might serve as support are few and disparate: 1) the Neptunalia closely follow the Lucraria; 2) they have a popular character; the participants build themselves huts of foliage (umbrae); 3) the sacrificial victim is the bull; 4) Nettuno has a goddess named Salacia; 5) at the first collective lectisternium (399 B.C.), Nettuno is paired with Mercurio. The temple of Nettuno stood near the Circo Flaminio. Another festival of his, and of Salacia and Venilia, was held on 1 December.
BIBLI: W. Werde Fowler, Roman festivals, Londra 1899, p. 185 seg.; G. Wissowa, Religion und Kultus der Römer, 2° ed., Monaco 1912, p. 225 seg.; St. Weinstock, in Pauly-Wissowa, XVI (1935), col. 2514 seg. Angelo Brelich