Greek Omens: Ancient Divination, Bird Signs, and Prophecies Explained

An omen or oionos (Greek for “bird”) was a natural phenomenon that supposedly could foretell an outcome in the future. To the Greeks, omens were messages sent from the gods to instruct humans. Zeus’s symbol was the eagle, while the raven stood for Apollo. There were a variety of natural phenomena that could occur commonly: eclipses, births, flocks of birds, and conditions of sacrifices. In the early Greek period, the main omen dealt with birds and their behaviors and acts. In the Iliad, Homer related several stories concerning prophecies foretold by the behavior of birds.

The poet Hesiod, in his Works and Days, referred to the wise man who can understand the signs of birds. The Greek augur who would undertake the observation of birds and sacrifices would face north. The augur would wear a white robe. When looking for favorable signs, the right, or east, was considered lucky.

During the time after the Mycenaean period, omens moved away from just the divination of birds and more toward hepatoscopy, observing the entrails, especially the livers, of sacrificial animals. This was derived from Eastern practices where it was prevalent, such as at Babylon, and was often used to predict the weather. The practice was then transmitted to the Hittites, and it was probably from them that the Greeks learned and began to practice it, especially in Ionia. The practice was represented on Greek vases.

One of the most famous natural phenomena used for telling the future was astronomical observations. The most famous story concerned Thales of Miletus, who supposedly foretold a solar eclipse, and the successful prediction soon frightened both sides into making peace. The historian Herodotus reported that Thales had predicted the event, and if so, it would have occurred on May 28, 585. In the story, Herodotus related that the Medes and Lydians were fighting a battle when the eclipse occurred, and both sides immediately stopped fighting and made a peace agreement. It is possible that the event was not a solar eclipse, but a lunar eclipse right before the battle in the morning; if so, two possible dates would be September 3, 609, and July 4, 587.

If he had predicted it correctly then Thales may have had knowledge of astronomy that he received from the Babylonians. Other eclipses were known to have had influenced outcomes. During the Peloponnesian War, Athens was fighting in Sicily when a total lunar eclipse occurred on August 27-28, 413. The Athenian general Nicias refused to flee after seeing the eclipse, thinking that it foretold disaster. This failure to sail away led to the Athenian defeat, so in essence he was correct.

Another type of omen, one that especially concerned evil portents, involved strange births. The most famous series of such events were recorded by Herodotus. The first referred to a birth of a lion to a concubine of Meles, the king of Sardis. He carried the cub around the walls except for one part, the section that Cyrus of Persia would later breach. His next references were to Xerxes’s invasion of Greece. One was the birth of a hare by a horse, meaning that he would march like a horse into Greece but would run away like a hare on his way back. Another concerned the birth of a foal by a mule that had both sets of genitals, something impossible that would predict disaster.

These stories were meant to show the arrogance or hubris of Xerxes and the superiority of the Greeks, who listened to the gods. The latter story from Herodotus concerned the omen where a fish came back to life as it was being cooked. The interpretation here was that the Persians could come back in power. Here, the Persian prisoner Artayctes, who desecrated the Trojan sanctuary, is punished, and like Xerxes, he is punished.

There were many centers in ancient Greece that helped to interpret omens. The most important of these were associated with Zeus and Apollo. Often the omen could be a plague or illness. When a plague descended upon Thebes, its king, Oedipus, asked how this omen should be interpreted; Teiresias, the seer, indicated that the plague would be lifted only when the murderer of the former king was punished. Upon discovering the truth that he himself had killed his father and married his mother, Oedipus exiled himself. Teiresias likewise told the new king, Creon, that the omens seen in Thebes after the battle between the sons of Oedipus were happening because one of the sons, Polyneices, must be buried. Creon responded by attacking Teiresias and his profession.

The Greeks, like other ancient societies, viewed omens as powerful forces that influenced society and individuals. The stories all show how omens predicted an event, either positive or negative, and could be interpreted and cast light on the future.