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Calendar 5: The Julian-Roman-Actual-1 Calendar

The Julian-Roman-Actual-1 Calendar (Number Change Day on January 1, the calendar, errors and late date corrections included, the Romans used from 45 B.C.E. through 9 B.C.E., actually 709 to 745 UAC)

This is the calendar the Roman Empire actually used with the timing of the leap years coming too frequent in its early years, whereas the envisioned Julian-Roman-1 calendar would have a leap year every four years beginning with the 45 B.C.E. year and the next would be 41 B.C.E., then in 37 B.C.E., etc. This Actual calendar would begin its first 40 or so years with a leap year every three years from 45 B.C.E. and onward, resulting in a correction mode in 8 B.C.E., with no leap years until 8 C.E., and matching the point where the dates for the envisioned Julian-Roman-1 calendar are located in real time.

I named this line of calendars the Romans used as the Julian-Roman-Actual-1 calendar line, due to the fact that it drifted from the original frequency of placement of years with leap year days for the first 40 years.

This is the calendar the Romans actually used (placement of leap year days not withstanding) during the years.

The Julian-Roman-Actual-1 (aka Julian-Roman-Kalends-Actual-1) calendar, including the erronaeous placement of leap year days that was used by the Roman Empire, was introduced in 709 UAC (or 45 B.C.E.)

The first year of this calendar was dated 709 U.A.C., based on the year Rome was founded.

When Julius introduced the calendar in 46 B.C., it was the year 708 AUC (or Ab urbe condita, meaning "from the founding year of the city of Rome".)

The years continued to be based from the year the city of Rome was founded.

It was invented to be effective January 1, 709 UAC, translated to Julian-Roman-Actual-1 year 45 B.C.

Since Jesus Christ wasn't born yet, there was no B.C./A.D. year dating system. The UAC year dating system for the year Rome was founded was used as the year of reckoning.

The calendar was designed to be an improvement of the Republican Calendar II, addressing serious issues with timing of the seasons and length of the months and years.

The Julian-Roman-Actual-1 Calendar used the Kalends Days counting down method carried over from the Republican Calendar II days.

Special Days of Kals were in effect with this variation of the calendar.

Beginning with the 709 AUD year, the old intercalary month was abolished. February would always have 28 days, with the 24th day of the month doubled to 48 hours on leap years. More on that later in this section.

The months of January, August and December expanded from 29 to 31 days, each gaining two days. In the case of August, where it started out with 30 days before losing one in the 8th century B.C.E., it got its missing day back after being missing seven centuries!

The months of April, June, September and November got their 30th day back after being missing for seven centuries!

  1. translation examples:
    1. The year 1 UAC = 753 B.C.
    2. The year 708 UAC = 46 B.C.
    3. The year 709 UAC = 45 B.C.
    4. The year 710 UAC = 44 B.C.
    5. The year 711 UAC = 43 B.C.
    6. The year 712 UAC = 42 B.C.
    7. The year 713 UAC = 41 B.C.
    8. The year 745 UAC = 9 B.C.
    9. The year 746 UAC = 8 B.C.
    10. The year 753 UAC = 1 B.C.
    11. The year 754 UAC = 1 A.D.
    12. The year 757 UAC = 4 A.D.
    13. The year 758 UAC = 5 A.D.
    14. The year 761 UAC = 8 A.D.
  2. The Julian-Roman-Actual-1 Calendar Design from 45 B.C.:
    1. The length of the months from 45 B.C.E. onward were the same as the ones we know today. The Julian reform set the lengths of the months to their modern values.
    2. The Months:
      1. Ianuarius -- 31 days (later renamed Januarius, then January)
      2. Februarius -- 28 days (29 days in leap year, later renamed February).
      3. Martius -- 31 days (later renamed March).
      4. Aprilis -- 30 days (later renamed April).
      5. Maius -- 31 days (later renamed May).
      6. Iunius -- 30 days (later renamed Junius, the June).
      7. Quintilis -- 31 days (renamed after Julius as Iulius in 44 B.C. after Julius was assassinated)
      8. Sextilis -- 31 days (renamed as Augustus in 8 B.C.)
      9. September -- 30 days
      10. October -- 31 days
      11. November -- 30 days
      12. December -- 31 days
    3. The Seasons:
      1. Winter solstice (Bruma) VIII Kal. Ianuarius (or Dec 25, the 8th day before January)
      2. Spring equinox (Vernal) VIII Kal. Aprilis (or Mar 25, the 8th day before April)
      3. Summer solstice () VIII Kal. Quintillis (or June 24, the 8th day before July)
      4. Autumnal equinox () VIII Kal. October (or September 24, the 8th day before October)
      5. Again, the Romans counted inclusive, down to one, not to zero.
  3. Leap Year Rules (corrected, removing Sacrobosco's theory):
    1. since there was no more intercalary month, as Caesar abolished it after the 46 B.C.E. calendar, there was a new system of inserting a single 24 hours to serve the purpose of realigning the calendar once every four years. It was done by expanding the VI Kal (Feb 24 during this era) to 48 hours (called Bissextile, not Bissextile Day). Historians can call the first 24 hours of the day (bis) VI Kal. Mart. or Bissextile Day proper.
    2. the placement of inserting an intercalary day (or Leap Year Day) instead of a month was introduced with the new design.
    3. the 48 hours forming the two days of February 24 (VI Kal) was called Bissextile, meaning, the doubling of the sixth day before Kalendae of March.
    4. Julius Caesar decreed that in leap years the "6th day before Kalendae of March" should be doubled. The doubling of the 6th day before Kalendae of March is the origin of the word bissextile. The earlier of the 24 hours matches the location of February 24 and the latter 24 hours matches February 25. The rest of Feberuary, 25-28 in non-leap years, gets shifted to the locations where February 26-29 would be.
    5. In modern day Februarys with 29 days, the actual traditional Leap Year Day would be February 24, not February 29.
    6. There were technically two VI Kal. Mart.'s (Feb 24's) in leap years when February was 29 days long. VI Kal. Mart. was called the 6th day before Kalendae of March. Caesar wanted 28 days in February every year even going as far as doubling the location of the 24th day of February so that the dates of the festivals in the five days of February would still lead into March the 1st without a 24 hour delay between the normal last day of February and the first for March.
    7. Why did Caesar choose to double the 6th day before Kalendae of March? It appears that the leap month Intercalaris/Mercedonius of the pre-reform calendar was not placed after February, but inside it, namely between the 7th and 6th day before Kalendae of March. It was therefore natural to have the leap day in the same position.
    8. Since February was 28 days long, and according to religious reasons, the rules for placing the leap year day was placed the day after Feb 23 (where the old intercalary month was inserted). Feb 23 was known as VII Kal (the seventh day before Kalendae of March), and it came one day before Feb 24, known as VI Kal (the sixth day before Kalendae of March)
    9. The earlier of the two Feb 24 (VI Kal) days might have been called Bissextile Day, bis VI Kal. Mar. or February 24 Posterior. The Feb 23 remained VII Kal. The Romans had the same date VI Kal twice in Leap Years.
    10. Terminalia was Feb 23, which was the end of the first part of February. Macrobius states during the Republican Calendar II years that the year began after Terminalia day ended with the Julian-Roman-Actual-1 calendar.
    11. February 24-28 (February 25-29 in leap years) formed the second part of February. Feb 24 (or Feb 25 during leap years) was Regifugium.
    12. Leap Days were supposed to be inserted five days before the end of February (between Feb 23 and 24) during this era. Although a Feb 29 is inserted at the end of February in modern day calendars, the traditional Leap Year Day was actually on Feb 24, while the normal days during non-leap years, Feb 24-28, were shifted one day back to be named Feb 25-29 during leap years.
    13. According to some scholars, the 709 AUD year (45 B.C.) was not a leap year. According to the way Romans counted down, was the year 43 B.C. the first year it had a leap year day? Some scholars say 44 B.C. was the first year.
    14. The last days of February with the leap year day looked like this:
      1. Feb 21, 22, 23, 24 Posterior or The Bissextile Day, 24, 25, 26, 27, 28
      2. or in early Julian calendar dating correspodence: IX Kal, VIII Kal, VII Kal, VI Kal Posterior or The Bissextile Day, VI Kal, V Kal, IV Kal, III Kal, pridie Kal
      3. March 1 was Kal I.
      4. Leap Day would be the equivlant of February 24, then February 25-29 would still be the same VI-pridie Kal days.
    15. Leap Year Day placement discrephancies:
      1. According to Julius, every four years was meant to be a leap year. The operators of the calendar, however, counted backwards inclusively, resulting in the insertion of a leap year day every three instead of four years.
      2. The calendar was operated correctly from Jan 1, 45 B.C.E. until the Feb 23, 42 B.C.E. where the priests inserted an intercalation day after that day one year too early.
      3. Julius's intention was to make the first intercalation after 45 B.C.E. on the day after Feb 23, 41, B.C.E., the end of the old Roman year.
      4. Leap years were supposed to be in 41 B.C., 37 B.C., 33 B.C., 29 B.C., 25 B.C., 21 B.C., 17 B.C., 13 B.C., 9 B.C., 5 B.C., 1 B.C., and 4 according to Julius Caesar who designed the calendar in 46 B.C.. No scholar agrees on when or where these Bissextile days were inserted.
      5. According to Scholar Ideler: The pontifices added a leap day every three years instead of every four, causing the calendar to go out of rhythm; the next leap day would occur in 8 AD where it would resume with the correct insertion of one leap year day every four years. After 9 B.C., three extra leap days, more than Julius intended, were inserted. Augustus corrected it by not having any more leap days until 8 AD when the calendar became realigned with Julius's intended calendar design, and leap year day was every four years thereafter.
      6. In 1999, an Egyptian papyrus was published which gives an ephemeris table for 24 B.C. with both Roman and Egyptian dates. From this it can be shown that the most likely sequence was in fact 44 B.C., 41 B.C., 38 B.C., 35 B.C., 32 B.C., 29 B.C., 26 B.C., 23 B.C., 20 B.C., 17 B.C., 14 B.C., 11 B.C., 8 B.C., AD 4, 8, 12 etc. This sequence shows that the standard Julian leap year sequence began in AD 4, the twelfth year of the Augustan reform.
      7. Reasoning: While the Julian-Roman-Actual-1 calendar itself began operation on Kal. Ian. A.U.C. 709, or 1 Ianuarius, 45 B.C., leap years were initially inserted every third year instead of every fourth, until the error was corrected by Augustus. After Caesar's death the pontiffs caused the leap day to be inserted "at the beginning of every fourth year instead of at its end" (i.e., since the Romans counted inclusively, every third year instead of every fourth), for 36 years, after which time there had been 12 leap days in a period that should have had 9. At that point, Augustus suspended intercalation for 12 years to compensate for the three extra leap days, and then resumed intercalation on the correct frequency.
      8. Theory: The pontifices inserted the intercalary day at the beginning of each fourth year instead of at its end, but might have been made at the end of each fourth year and before the beginning of the fifth.
      9. Many scholars disagree on when the actual leap years happened between 45 B.C. and 8 B.C. Some start the first intercalary day between 45 to 42 B.C. with the last between 11 to 8 B.C., with the leap year resuming between 4 and 8 (one Scholar says 7) AD.
  4. Four variations of this Julian-Roman-Actual-1 calendar
    1. Julian-Roman-Actual-1 (aka Julian-Roman-Kalends-Actual-1), days counting down to Nones, Ides and Kalends, and the year of reckoning is 753 B.C., the year Rome was founded. This was the original day counting direction/naming and year of reckoning that was intended to replace the Republican Calendar II in 45 B.C.E.
    2. Julian-Kalends-Actual-1 (aka Julian-Christ-Kalends-Actual-1), days counting down to Nones, Ides and Kalends, and the year of reckoning is 1 B.C., the year Christ was conceived by Mary. This was conceived in the middle of the first millenium as it replaced the reckoning year of Rome.
    3. Julian-Countup-Actual-1 (aka Julian-Christ-Countup-Actual-1), days counting up from 1 to the number representing end of the month, and the year of reckoning is 1 B.C., the year Christ was conceived. This is the standard since the middle ages.
    4. Julian-Roman-Countup-Actual-1 (aka Julian-Roman-Countup-Actual-1), days counting up from 1 to the number representing end of the month, and the year of reckoning is 753 B.C., the year Rome was founded. I don't believe this calendar was ever used, but it's here for comparision with the other three calendar reckoning/day counting variations.
    5. All four calendars above can be stretched backward to be proleptic.

Roman Day to Numeric Day of Month Equivalent Chart (45 B.C.E. and later)

Months and Days added (10 yearly days plus one leap year day, expanding calendar on normal years from 355 to 365 days, and to 366 on leap years):
Martius, Maius, Quintillis, October: no changes
Iunius, Sextillis, December (expanded from 29 to 31 days): XIX Kal. on the 14th and XVIII Kal. on the 15th, other days pushed back two days to the 16th through 31st.
Aprillis, Iunius, September, November (expanded from 29 to 30 days): XVIII Kal. on the 14th, other days pushed back one day to the 15th through 30th.
Februarius (28 days in non-leap years): no changes, but the month is no longer truncated to 23 days during leap years.
Februarius (29 in leap years): bis VI Kal. (Bissextile Day, the first two hours of the doubling of VI Kal. on the 24th, followed by the rest of the regular days pushed back to 25th through 29th)

Months and Days dropped:
Mercedonius (27 days in month): Kal., IV Non. to Non., VIII Id. to Id., XV Kal. to prid. Kal. (1st through 27th)
Mercedonius (28 days in month): Kal., IV Non. to Non., VIII Id. to Id., XVI Kal. to prid. Kal. (1st through 28th)
Intercalaris Prior (33 days, assuming that Nones is on the 7th since the month is rather long): Kal., VI Non. to Non., VIII Id. to Id., XIX Kal. to prid. Kal. (1st through 33rd)
Intercalaris Posterior (34 days, assuming that Nones is on the 7th since the month is rather long): Kal., VI Non. to Non., VIII Id. to Id., XX Kal. to prid. Kal. (1st through 34th)

If people were born on the days that were seen in 46 B.C.E. or earlier, but are no longer seen, what days did they celebrate their birthdays in 45 B.C.E. and later?

Numeric Day of MonthMart. Mai. Quin. Oct. (31 days)Ian. Sext. Dec. (31 days)Apr. Iun. Sept. Nov. (30 days)none (29 days)Feb (29 days, with bis)Feb (28 days)
1Kal. Kal. Kal. Kal. Kal. Kal.
2VI Non. IV Non. IV Non. IV Non. IV Non. IV Non.
3V Non. III Non. III Non. III Non. III Non. III Non.
4IV Non. Prid. Non.Prid. Non.Prid. Non.Prid. Non. Prid. Non.
5III Non. Non. Non. Non. Non. Non.
6Prid. Non. VIII Id. VIII Id. VIII Id. VIII Id. VIII Id.
7Non. VII Id. VII Id. VII Id. VII Id. VII Id.
8VIII Id. VI Id. VI Id. VI Id. VI Id. VI Id.
9VII Id. V Id. V Id. V Id. V Id. V Id.
10VI Id. IV Id. IV Id. IV Id. IV Id. IV Id.
11V Id. III Id. III Id. III Id. III Id. III Id.
12IV Id. Prid. Id. Prid. Id. Prid. Id. Prid. Id. Prid. Id.
13III Id. Id. Id. Id. Id. Id.
14Prid. Id. XIX Kal. XVIII Kal.XVII Kal. XVI Kal. XVI Kal.
15Id. XVIII Kal.XVII Kal. XVI Kal. XV Kal. XV Kal.
16XVII Kal. XVII Kal. XVI Kal. XV Kal. XIV Kal. XIV Kal.
17XVI Kal. XVI Kal. XV Kal. XIV Kal. XIII. Kal. XIII. Kal.
18XV Kal. XV Kal. XIV Kal. XIII. Kal.XII Kal. XII Kal.
19XIV Kal. XIV Kal. XIII Kal. XII Kal. XI Kal. XI Kal.
20XIII Kal. XIII Kal. XII Kal. XI Kal. X Kal. X Kal.
21XII Kal. XII Kal. XI Kal. X Kal. IX Kal. IX Kal.
22XI Kal. XI Kal. X Kal. IX Kal. VIII Kal. VIII Kal.
23X Kal. X Kal. IX Kal. VIII Kal. VII Kal. VII Kal.
24IX Kal. IX Kal. VIII Kal. VII Kal. bis VI Kal.VI Kal.
25VIII Kal. VIII Kal. VII Kal. VI Kal. IV Kal. V Kal.
26VII Kal. VII Kal. VI Kal. V Kal. V Kal. IV Kal.
27VI Kal. VI Kal. V Kal. IV Kal. IV Kal. III Kal.
28V Kal. V Kal. IV Kal. III Kal. III Kal. Prid. Kal.
29IV Kal. IV Kal. III Kal. Prid. Kal.Prid. Kal. --
30III Kal. III Kal. Prid. Kal.-- -- --
31Prid. Kal.Prid. Kal.-- -- -- --
  1. Id. = Idus = Ides
  2. Non. = Nonae = Nones
  3. Kal. = Kals = Kalendae
  4. Prid. = pridie
Calendar History Main Page Calendar 1: The Romulus Calendar I Calendar 2: The Republican Calendar I Calendar 3: The Republican Calendar II Calendar 4: The Republican Transitional Calendar Calendar 5: The Julian-Roman-Actual-1 Calendar Calendar 6: The Julian-Roman-Transitional-1 Calendar Calendar 7: The Julian-Roman-1 Calendar Calendar 8: The Julian-Kalends-1 Calendar Calendar 9: The Julian-1 Calendar Calendar 10: The Gregorian Calendar Dual Dating Date Confusion Definition of Days on the Calendars Definition of Calendars: Others Old, New and Unknown Styles Leap Year Error on the Julian-Roman-Actual-1 Calendar What Calendars Each Country Was Using Gregorian-Julian Differences By Century New Years Days Addenda Day and Year Measurements Calendar Varieties-Gregorian Calendar Varieties-Julian Calendar Varieties-Other Years Converted From Julian Period Day Lining Up Julian Dates Between Earth and Mars The Martian Calendar of Earth Converting From the Julian Period Date Creating a Julian Period Day Database File Truncating Answers Conversion Between Julian-1 and Gregorian Calendars Create a Calendar Leap Year Day Comparisons Swedish Calendar 1700-1712 Fractions of Years, Etc.
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