Calendars and Chronology

Greek cities each had their own distinctive calendars, which represent various attempts to marry the incommensurate cycles of the Moon and the Sun.

Date: c. 1370-31 b. c.e.

Category: Mathematics; astronomy and cosmology

The Bronze Age The earliest evidence for Greek calendars comes from the Linear B tablets recovered from Knossos on Crete (c. 1370 b. c.e.) and Pylos in southern Greece (c. 1200 b. c.e.). They represent ritual calendars, in which the offerings to be made to the gods were listed month by month. The word for “month” is me-no, which suggests a relationship with the Moon and therefore a lunar calendar, but how this system might have been correlated with the seasonal, solar year is unknown. From Knossos are preserved the names of eight months, and from Pylos three, but the two sites share none in common. All apparently derive from gods or localities, and four names resemble later historical months—di-wi-jo (Dios), ra-pa-to (Lapato), di-pi-si-jo (Dipsios), and ka-ra-e-ri-jo (Klareon)—but this is the only evidence for any continuity.

Homer and Hesiod Within Homer’s Iliad (c. 750 b. c.e.; English translation, 1611) and Odyssey (c. 725 b. c.e.; English translation, 1614) are reflections of the use of the Sun as a measure of the seasonal year, although lunar months are also referred to, for instance as a means of counting the length of a pregnancy. While no calendar as such appears, the risings and settings of stars are used as signals for periods in the seasonal year.

This mechanism is more developed in Hesiod’s Erga kai Emerai (c. 700 b. c.e.; Works and Days, 1618), which is partly an account of the agricultural year. The poet provides ten observations of five stars or constellations, which help distinguish four seasons. Accompanying this star-lore are other signs from the natural world, such as the arrival of migrating birds.

The Moon too is occasionally used to signal the proper time for farming activities. Star-based almanacs remained in use throughout the Greek and Roman periods, providing historians such as Thucydides (c. 459-c. 402 b. c.e.) with fixed points to which they could attach events more securely than if they relied solely on the discordant, local state calendars.

Classical Greek Calendars The city-states of Greece all kept lunar calendars, but the start of the year differed from city to city. Each city began its year with the first new Moon after a key point of the solar year, but this could be the summer or winter solstice or the spring or autumn equinox. This combination of lunar and solar phenomena made the beginning of the year mobile within a certain period of time, exactly like Christian Easter. A mixture of observation and schematic calculation seems to have been used in deciding when a month started and when it ended, with the start being marked by the evening sighting ofthe new Moon’s crescent.

The Athenian year began after the summer solstice, midway through a Julian year. The names of the months—Hekatombaion, Metageitnion, Boedromion, Pyanepsion, Maimakterion, Poseideon, Gamelion, Anthes-terion, Elaphebolion, Mounichion, Thargelion, and Skirophorion—reflect religious festivals that took place in the month. A year consisted usually of twelve lunar months, with an occasional thirteenth added (or intercalated) in an attempt to bring the lunar year of354 days, with its alternating months of 30 and 29 days, into alignment with the solar year of 365.25 days.

Various systems of intercalation were devised to attain this realignment, notably the eight-year cycle and the nineteen-year (or Metonic) cycle, the latter named after the Athenian Meton, who invented it in the 430’s b. c.e. In the eight-year cycle, three of the lunar years were given an extra month, while in the Metonic cycle seven years gained one. The four-yearly games at Delphi and Olympia were governed by eight-year cycles, while Athens at times regulated its calendar with the Metonic cycle, with intercalary months added every second, fifth, eighth, tenth, thirteenth, sixteenth, and eighteenth year.

It is impossible to synchronize the Greek cities’ calendars except in ideal terms. Interstate decrees, financial statements, and even slave manumissions are particularly helpful in establishing broad synchronisms, as they often include correspondences between the calendars of two cities.

Hellenistic Calendars As a result of the conquests of Alexander the Great, the Macedonian calendar not only was widespread throughout the Greek world but also was assimilated into Egypt and the former Persian Empire. Its months were Dios, Apellaios, Audnaios, Peritios, Dystros, Xanthikos, Artemisios, Daisios, Panemos, Loios, Gorpiaios, and Hyper-beretaios. The new year began after the autumn equinox. The Persian Empire used the old Babylonian lunisolar calendar, regulated by its own independent nineteen-year cycle. The Macedonian calendar slotted into this much older, but very similar, system without any loss. In Egypt, however, a calendar of 365 days was used, with twelve months each of thirty days being followed by five extra (epagomenal) days. The Macedonian calendar was absorbed into this system but lost its lunar character entirely, as the Macedonian months were made to fit the regular Egyptian ones.

Chronology In Athens, one political year was distinguished from another on official documents by the names of the secretary of the first month’s standing-committee (prytany) of the council. Lists of the principal annual magistrates (archons) were also drawn up, allowing events in individual years to be attached to the archonship. Relative chronology could be constructed from this system. For example, the Parian Marble (264/263 b. c.e.) lists various events, dating them from the year of its carving in “the archonship of Astyanax(?) at Paros and Diognetos at Athens.”

Different eras existed. There were “liberation” eras; for example, the era of Tyre started in 126/125 b. c.e., when the city broke free of Seleucid rule, and lasted into the seventh century c. e. A king’s regnal years could also distinguish one year from the next; for example, the capture of Babylon in 312 b. c.e. marked the first year of the reign of Seleucus I Nicator. Augustus’s victory at Actium in 31 b. c.e. became the start of another era for some cities. The best-known era is that of the Olympiads, the four-year periods of the Olympic Games, starting traditionally in 776 b. c.e. This was formulated by Timaeus (c. 350-260 b. c.e.) and Eratosthenes (c. 285-c. 205 b. c.e.). As the Olympic year began in midsummer, however, it straddled the second half of one Julian year and the first half of the next; for example, the third year of the sixth Olympiad (Ol. 6, 3) is equivalent to 754/753 b. c.e.

Further Reading

Bickerman, E. J. Chronology of the Ancient World. Rev. ed. London: Thames and Hudson, 1980.

Hannah, Robert. Greek and Roman Calendars: Constructions of Time in the Classical World. London: Duckworth, 2005.

Samuel, Alan E. Greek and Roman Chronology: Calendars and Years in Classical Antiquity. Munich, Germany: Beck, 1972.

Robert Hannah

See also: Athens; Crete; Eratosthenes of Cyrene; Hesiod; Historiography; Linear B; Olympic Games; Seleucus I Nicator; Thucydides.