The Sibylline Books were developed early in Roman history as a means of state divination and as a senatorial mechanism for effecting collective religious responses to critical situations.

The Sibylline Books were a collection of oracles written in Greek hexameters that were carefully guarded in ancient Rome and were consulted in times of great distress as a result of war, famine, pestilence, or other public calamity. Dionysius of Halicarnassus
Tarquinius Superbus, Lucius
Varro, Marcus Terentius

The Sibyls, from whom the adjective “Sibylline” is derived, were women oracles who gave responses to questions posed to them. The etymology of “Sibyl” is unknown, although numerous attempts have been made in ancient and modern times to explain it. The Sibyls originated in Asia Minor during the seventh century b.c.e. and spread from there to various sites throughout the Mediterranean world. The philosopher Heraclitus of Ephesus (c. 540-c. 480 b.c.e.) was the first writer to refer to women of this type, but he knew of only one Sibyl. Heraclides Ponticus (c. 388-c. 310 b.c.e.), a philosopher and writer, was aware of two Sibyls, and later authors mention three, four, eight, ten, and twelve of them, or leave the number indefinite. The most famous listing of these seers is that given by Marcus Terentius Varro in his Antiquitates rerum humanarum et divinarum libri XLI (first century b.c.e., now lost; of matters human and divine), in which he names all sorts of Sibyls: Persian, Libyan, Delphic, Cimmerian, Erythraean, Samian, Cumaean, Hellespontic, Phrygian, and Tiburtine.

The Sibyls could be consulted on a private or public basis, and collections of their responses were compiled and circulated. One of these collections reached Rome toward the end of the sixth century b.c.e. There, it received official approval and came to be known as the Libri Sibillini, or Sibylline Books.

The famous story connected with the advent of these books is a legend devised to increase their prestige. The story is related by both Greek and Latin authors with some minor alterations in detail. The fullest account is that found in Dionysius of Halicarnassus, who taught history and rhetoric in Rome. According to him, Rome, through the favor of some divinity, was the recipient of wonderfully good fortune during the reign of Lucius Tarquinius Superbus (also known as Tarquin the Proud). A foreign woman tried to sell the king nine books of Sibylline oracles. When he refused to buy them, she burned three of the nine books and then offered him the remaining six at the original price. Rebuffed again, she burned three more of the books. When she finally offered the remaining three for the same price as the original nine, the baffled king asked the advice of his augurs, or official diviners. These augurs decided by certain signs that he had rejected a divine blessing in not buying all the books and urged him to purchase at least those that remained.

Tarquinius appointed two prominent men to guard the books and gave them two public slaves to assist them in their task. Dionysius states that these books were kept in a stone chest beneath the temple of Jupiter on the Capitoline hill until the time of the Roman Civil War in 91-88 b.c.e., and that they perished in the fire that destroyed the temple in 83 b.c.e. The books were replaced with oracles gathered from other Italian cities, from Erythrae in Asia Minor, and other places. According to Dionysius, these oracles were the most guarded possession of the Romans, whether sacred or profane, so that the senate decreed that they could be consulted only during times of strife and misfortune in war or when some baffling prodigy or apparition appeared.

Some attempts have been made to derive the Sibylline Books from Etruria because of their resemblance to the Libri fatales, or Books of Fate, which are assumed to be of Etruscan origin. This title, however, is a generic term used for both Etruscan and Greek rituals. It seems more probable that the oracles were brought to Rome from Cumae, whence they had originally come from Erythrae. Unlike the Greeks, who freely allowed private persons as well as public officials to consult their oracles and even permitted private copies of the responses to be made, the Romans surrounded the books with great secrecy and restricted their use to state officials. Not even the priests in charge could consult them without a special order of the senate.

Scholars have traditionally credited the Sibylline Books with the progressive introduction of Greek and Eastern deities and modes of worship into Rome. Among the gods introduced in this manner were Demeter, Dionysus, and Kore under the Latin names Ceres, Liber, and Libera; the most famous of all was Cybele. Among the rites introduced were the lectisternium, or public offering of food to the gods as they were displayed on pillows or couches; the supplicatio, a general thanksgiving in honor of the gods; and the ver sacrum (sacred spring), a sacrifice of all fruits and animals produced in a particular spring. In a paper presented to the American Philosophical Association’s annual meeting in 1994, Eric Orlin showed that the introduction of some of the so-called Greek cults and practices represented the senate’s attempt to strengthen ties with south Italy and Sicily and that the Sibylline Books were thus used to sanction senatorial diplomatic policy rather than to serve as a mechanism for importing foreign religious customs.

The original priesthood in charge of the books, the Duoviri sacris faciundis, was increased from two to ten individuals, known as the Decemviri, and then to fifteen, the Quindecimviri. This priesthood formed one of the four major priestly colleges. As part of his religious reform, Augustus (r. 27 b.c.e.-14 c.e.) ordered a revision to be made of the oracles and had them transferred to the temple of Apollo on the Palatine hill, but by then their days of influence had largely passed. Although interest in them revived under the emperors Aurelian and Julian the Apostate, the Sibylline Books were reportedly burned during the reign of Honorius (r. 393-423 c.e.) by order of his general Stilicho.

• Beard, Mary, and John North. Pagan Priests. Ithaca, N.Y.: Cornell University Press, 1990. A collection of essays that focus not only on Roman divination and priesthoods but also on the activities of other pagan societies.
• Boyce, Aline. “The Development of the Decemviri Sacris Faciundis.” Transactions of the American Philological Association 69 (1938): 161-187. Provides an overview of the rituals prescribed by the priesthood charged with consulting the Sibylline Books.
• Coulter, Cornelia. “The Transfiguration of the Sibyl.” Classical Journal 46 (1950-1951): 65-71, 78, 121-126. The author surveys the changing role of the books over time.
• Momigliano, Arnaldo. “Sibylline Oracles.” In The Encyclopedia of Religion. Vol. 13. New York: Macmillan, 1987. An account of Sibylline oracles in different religious traditions.
• North, John. “Religion in Republican Rome.” In The Rise of Rome to 220 b.c.
  Vol. 7, part 2 in The Cambridge Ancient History, edited by F. W. Walbank et al. New York: Cambridge University Press, 1989. North provides an overview of the development of Roman cults, games, and traditions during the course of the Republic.
• Parke, H. W. Sibyls and Sibylline Prophecy in Classical Antiquity. London: Oxford University Press, 1988. A study of Sibyls and their prophecies in religion, poetry, and politics of the ancient world.
• Turcan, Robert. The Gods of Ancient Rome: Religion in Everyday Life from Archaic to Imperial Times. Translated by Antonia Nevill. New York: Routledge, 2001. This overview of Roman religion is divided into sections on family religion, state religion, and imperial religion, providing a context for understanding the use of oracles in Roman life.

Heraclitus of Ephesus; Flavius Stilicho; Marcus Terentius Varro. Sibylline Books