Question: The Julian Calendar - Julius Caesar Reformed the Calendar
Who is the Julian of the Julian Calendar and what is the Julian Calendar?
Answer: The Julian Calendar is named for its creator, Julius Caesar. Among the offices he held, Caesar was Pontifex Maximus, the highest Roman priest. The calendar was the province of the priests because it was they who annually picked the dates of the religious festivals. By 46 B.C., what should have been autumn harvest festivals were lining up with the summer. This would be a problem because you can't harvest what hasn't yet grown. When Caesar returned from Egypt to Rome that year, he fixed the Roman calendar, probably based on what he'd learned from the astronomer Sosigenes of Alexandria.
The year of Caesar's fix was a mess: about 445 days long. Some called it "the year of confusion," according to the William Smith, A Dictionary of Greek and Roman Antiquities, entry on the calendar. Macrobius (A.D. 395–423), the Roman grammarian known for describing the Roman winter holiday of Saturnalia, had a different label for 46 B.C. He called it the last year of confusion.
Caesar set up a modern-looking regular year with 365 days, plus a fix for the leap year every four years. The modern calendar is said to be 365.25 days long, so this looks equivalent, but it's not. This fix caused confusion because the Romans used inclusive counting, instead of exclusive counting, as we use. So, by the time of Augustus (ruled c. 31 B.C. - A.D. 14), the newly-reformed calendar already required fine tuning.
Caesar lined up New Year's Day with the Kalends (the first day) of January. The Kalends of January is roughly the time when daylight is at its shortest. New Year's Day had been March 1, although alongside the official religious calendar, there was a secular calendar that already started in January.
A side note: The roman calendar was divided into periods based on the cycle of the moon known as the Kalends, Ides, and Nones. Days of this calendar are counted backwards from the next Kalends, Ides, or Nones. This is not a week-based calendar. However, the published secular calendar included the letters A-G for the "Nundinae" or 8-day market weeks. See: "The Superstitions about the Nundinae," by Van L. Johnson. The American Journal of Philology, Vol. 80, No. 2. 1959, pp. 133-149.
Julian Calendar Sources
The entry from the Smith dictionary says the following are ancient sources on the Julian Calendar:- Plutarch (Caes. c. 59),
- Dion Cassius (XLIII.26),
- Appian (De Bell. Civ. II. ad extr.),
- Ovid (Fasti, III.155),
- Suetonius (Caes. c. 40),
- Pliny (H.N. XVIII.57),
- Censorinus (c. 20),
- Macrobius (Sat. I.14),
- Ammianus Marcellinus (XXVI.1),
- Solinus (I.45).
Suetonius writes the following on the subject of Julian calendar reform:
Then turning his attention to the reorganisation of the state, he reformed the calendar, which the negligence of the pontiffs had long since so disordered, through their privilege of adding months or days at pleasure, that the harvest festivals did not come in summer nor those of the vintage in the autumn; and he adjusted the year to the sun's course by making it consist of three hundred and sixty-five days, abolishing the intercalary month, and adding one day every fourth year. Furthermore, that the correct reckoning of seasons might begin with the next Kalends of January, he inserted two other months between those of November and December; hence the year in which these arrangements were made was one of fifteen months, including the intercalary month, which belonged to that year according to the former custom.
Read more in Roman Calendar Terminology.
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