The nine Muses
The most famous Greek nine is the group of the nine Muses. Hesiod, composing the Theogony around 700 BCE, names them as Kleio, Euterpe, Thaleia, Melpomene, Terpsichore, Erato, Polyhymnia, Ourania and Kalliope, daughters of Zeus and Mnemosyne, the personification of memory. He also gives the origin of the number. In his account, Zeus lay with Mnemosyne in Pieria for nine nights, away from the other gods, and after a year she bore nine daughters, “of one mind”. The number is built into the story of their birth.
The Muses are not always nine in the evidence. Homer invokes the Muse, or Muses, at the start of the Iliad and the Odyssey without giving a number, and the one place the Odyssey says nine is a scene where they sing a lament over the dead Achilles. Some regional traditions are reported to have spoken of fewer, such as three, though the later sources for this are thinner. The fixed nine became standard in Greek and then Roman literature. The assignment of each Muse to a particular art, such as Kalliope to epic poetry and Ourania to astronomy, developed later, mostly in the Hellenistic and Roman periods, and Hesiod gives them no separate departments. The Romans often identified the Muses with their own Camenae, older spring goddesses, and carried the Greek nine into Latin poetry.
Nine days and nine nights in epic and hymn
The Greek poets used nine as a standard span of time. Examples include:
- The plague in the Iliad. At the opening of the poem, Apollo’s arrows fall on the Greek army for nine days before Achilles calls an assembly.
- Mourning Hector. At the end of the Iliad, Priam tells Achilles that the Trojans will mourn Hector in their halls for nine days and bury him on the tenth, and the poem has them gather wood for the pyre over the same nine days.
- Odysseus at sea. In the Odyssey, Odysseus tells of drifting for nine days after his ship is wrecked, before reaching Calypso’s island on the tenth.
- Demeter’s search. In the Homeric Hymn to Demeter, the goddess wanders the earth with torches for nine days looking for her daughter Persephone.
- Leto’s labour. In the Homeric Hymn to Apollo, Leto suffers labour pains for nine days and nine nights on Delos before Apollo is born.
- The fall from heaven. Hesiod writes that a bronze anvil would fall nine days and nights from heaven to earth and take a tenth to reach Tartarus, giving a picture of the depth of the underworld.
None of these passages explains why the poets chose nine, so any reading is an interpretation. A common view among classicists is that nine, as just short of the round ten, worked as a conventional “long time”, and that the poets wanted a span that felt substantial but still finished at the tenth day. The pattern also fits the idea of nine as three times three, a habit associated with the rule of three in stories. Both are modern suggestions and not statements from the sources.
Nine in the underworld
Hesiod’s account of the river Styx shows another nine. An oath-breaking god is punished by lying breathless for a full year and then excluded from the company of the gods for nine years. Centuries later, Virgil’s Aeneid describes the river Styx winding around the underworld nine times. Greek and Roman writers did not agree on a single geography of the afterlife, and Virgil is writing literature rather than reporting doctrine.
Roman nines
Roman religion and custom had its own nine-day uses. One was the novendiale, a nine-day period of ritual, which according to Roman historians such as Livy was called for after prodigies such as a shower of stones, and also connected to funerary observance after a death. Another was the market day. The Romans held a market every eighth day by modern counting, but they counted inclusively, so the day was the ninth from the last one; the Latin name nundinae reflects that “ninth-day” idea. The market cycle ran alongside the months of the Roman calendar. Roman writers also express a preference for odd numbers, often summarised as odd number luck, and the nine-day periods fit that habit, though the sources do not link them directly.
What the examples show
There is no evidence in these sources of a single Greek or Roman doctrine about the number nine. Instead, we see a handful of independent uses: nine as a family (the Muses), nine as a conventional length of time in epic and hymn, nine as a measure of depth or distance (the fall from heaven, the course of Styx), and nine as a period of mourning or ritual. Some of these may be related by habit, since poets borrow forms from one another, and others may be coincidence. Modern claims that nine had a hidden power for Greeks and Romans go beyond what the texts say. They are best seen as stories about how those authors measured time and marked completion, and about how long customary mourning periods were expected to last.