1. The Roman Calendar
Yes, It’s Complicated!

2. Kalendars Early Civs based calendar on Lunar cycle.
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Kalendars
Early Civs based calendar on Lunar cycle.
13 months, 28 days each
Lunar cycle is still used: Where?
Lunar cycle does not follow Earth Cycle

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Anni Romani
The Romans were not good at keeping track of years. They got better as time went on.
Early: Only 10 months per year.
The winter months (Jan and Feb) were not counted on the calendar as days.
Numa Pompilius added January and February to the end of the year.
March 1st was New Year Day.

4. So month names were misnomers.
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So month names were misnomers.
They were off by two months: October was the 10th month and not 8th month.
Year was still only 355 days.
So occasionally, they added leap day to end of the year:
Feb 29th
Occasionally they added a leap month (intercalenary) containing as many days as they needed to get the year back on schedule.
The Pontifices determined all this.

5. Annus Dating System The Romans did it two ways:
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Annus Dating System
The Romans did it two ways:
a) According to the names of the two consuls. Consuls ruled for 1 year terms. (You may consult internet for entire list of consuls.)
b) Years since the founding of Rome = Ab Urbe Conditu (AUC).
Rome was founded in 753 bc by Romulus.

6. Iulius Caesar Reforms Calendar
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Iulius Caesar Reforms Calendar
By IC’s time the calendar was way off again. So he reformed the calendar.
To set year correct: year 46 bc was 455 days long. “Last Year of Confusion”
Starting in 45 bc, the year was designated as 365 ¼ days long. Days were added to months so = 365 days. (same as length now)
Leap day every 4th year.

7. FYI: Gregorian calendar:
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FYI: Gregorian calendar:
Despite Caesar’s best effort, the year was off by 11 minutes a year. Which adds up to 1 day every 134 years.
So by Pope Gregory XIII in 1582 the year was off by ten days.
He reset the calendar and added new rules for when NOT to have leap days to keep the calendar in synch.

8. The Roman Dies The Roman dies began at sunrise.
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The Roman dies began at sunrise.
Daylight was divided into 12 horas (hours). Problem?
Summer hours were longer than Winter hours.
(PGH on the Solstice: Summer 75 minute hour, Winter 46 minute hour.)
Noon: 6th hour, Sunset: end of 12th hour.
Meridies: the term for Noon: am pm

9. The Roman Nox Nox: harder to tell time at night.
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The Roman Nox
Nox: harder to tell time at night.
Most people stayed in and went to bed early.
Nox divided into 4 vigils (watches)

10. Menses Romani Menses Romani are difficult to follow. 3 main days:
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Menses Romani
Menses Romani are difficult to follow.
3 main days:
--Kalends  1st day of the month
-- Ides 13th day of month 15th day of Month in March, July, October and May
-- Nones 9 days before the Ides

11. Dies Calendae The days of the month were numbered.
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Dies Calendae
The days of the month were numbered.
They counted DOWN until the K, N or I.
Pridie = the day before the K, N, or I
a.d. = Ante dies = days before
Also days marked with letters A – H
Each year a letter would be marked in RED and represented MARKET DAY
Market Day was called Nundiae (9th day)

12. Example of Month: F 1: Kalends H 11: ad 3 I Jan B 21: ad 12 K Feb
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January , August or December
F 1: Kalends
H 11: ad 3 I Jan
B 21: ad 12 K Feb
G 2: ad 4 N Jan
A 12: Pridie Idus
C 22: ad 11 K Feb
H 3: ad 3 N Jan
B 13: Idus
D 23: ad 10 K Feb
A 4: Pridie Nonae
C 14: ad 19 K Feb
E 24: ad 9 K Feb
B 5: Nonae
D 15: ad 18 K Feb
F 25: ad 8 K Feb
C 6: ad 8 I Jan
E 16: ad 17 K Feb
G 26: ad 7 K Feb
D 7: ad 7 I Jan
F 17: ad 16 K Feb
H 27: ad 6 K Feb
E 8: ad 6 I Jan
G 18: ad 15 K Feb
A 28: ad 5 K Feb
F 9: ad 5 I Jan
H 19: ad 14 K Feb
B 29: ad 4 K Feb
G 10: ad 4 I Jan
A 20: ad 13 K Feb
C 30: ad 3 K Feb
D 31: Pridie K Feb

13. 7 day week: Iulius Caesar again:
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7 day week: Iulius Caesar again:
Romans did not really have weeks like we do, but had market cycles: 8 or 9 days
Iulius Caesar changed the market cycles to be 7 days or an octave.
Each day was dedicated to the 7 main heavenly bodies.
Sun, Moon and planets.
5 Planets: (day of _____) Mars, Mercury, Jupiter, Venus, Saturn
Romance Languages still use these names.

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Actual Roman Calendar

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