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Calendar 7:The Julian-Roman-1 Calendar

The Julian-Roman-1 Calendar (calendar used from 5 C.E. (758 UAC), using corrected Leap Year Day frequency, Number Change Day on January 1)

Beginning on March 1, 4 C.E., after the recalibration of the timing of the calendar achieved by using the temporary Julian-Roman-Transitional-1 calendar from 8 B.C.E. through Feb 28 that had no years with extra 24-hour "leap" days, the Julian-Roman-1 calendar set to the intended timing of the months and days envisioned by Julius Caesar began at this point. The temporary order of having no leap-years for 12 years had come to an end as the Roman's calendar caught up with the timing of the proleptic Julian-Roman-1 calendar.

The Julian-Roman-1 as I name it is considered to be the calendar Julius Caesar envisioned with the frequency of leap years every fourth year (every "five" according to the way the Romans counted backwards to one.) The days and months of this calendar line up with the original planning of the spacing of leap years that Caesar asked for. It corrected the issues of frequency of leap year days beginning with the year 8 C.E.

It uses the year Rome was founded as its reckoning year. Since nobody had yet thought of reckoning the calendar based on the year Jesus Christ was conceived until centuries later, the years since Rome was founded was used to count up the years. This calendar variation may still be used today for some purposes as its dates line up with the variations of this calendar design.

There is no year zero.

Special Days of Kals was in effect. The Julian-Roman-1 Calendar used the Kalends Days counting down method carried over from the Republican Calendar II days.

Two other variations of this calendar that began to be used gradually are the Julian[-Christ]-Kalends=1 calendar, which set the year of reckoning to 1 B.C.E., and the Julian[-Christ]-1 calendar, which replaced the Nones-Ides-Kalends method of numbering months to a count-up method. All three of the calendar variations's dates match those of each other's counting up from the first day of their months, though the naming of the days may be different.

This Julian-Roman-1 calendar and its variations are based on the month formats of the revised Julian-Roman-Actual-1 calendar. All of the lengths of the months match up with each other.

This Julian-Roman-1 calendar and its variations are all proleptic prior to March 1, 4 C.E. When historians date events backwards into the B.C. era, they normally extend the Julian-1 calendar backward in time. This extended calendar is known as the "Julian Proleptic Calendar", or simply, the calendar that hasn't been invented yet during the earlier times.

The two variations of the Julian-Roman-1 calendar share most similarities, except for placement and naming of the intercalary "leap" day, between them, which will be explained later on separate pages about them. In the years prior to 1 C.E. on the proleptic calendars, a year in B.C.E. is a leap year, if the absolute value of the B.C.E. year minus one (examples 5-1, which is four, 9-1, which is 8 etc.) is divisible by 4. This is the natural extension of the Julian leap year rules.

Due to the imperfect design, this This Julian-Roman-1 and its variations design were long by three days every 400 years, resulting in the future calendar years beginning later and later. Also, the calendar's length resulted in the proleptic calendar years to begin earlier and earlier when going back in time, and later and later when going forth in time.

  1. Calendar Design:
    1. The length of the months from 8 B.C. onward and backward were the same as the ones we know today.
    2. Notes: Kalendae was always on the first of the month.
    3. also note that the days of Nones and Ides remain unchanged even with the changes of the calendar. The Nones and Ides fell on the 5th and 13th days of the months shorter than 31 days, as well as on the months of Ianuarias, Augustus and December that had been expanded from 29 to 31 days.
    4. The original four months with 31 days, Martius, Maius, Iulius and October, still had the Nones on the 7th and the Ides on the 15th.
    5. The Months:
      1. Ianuarius -- 31 days (Nones on the 5th, Ides on the 13th)
      2. Februarius -- 28 days (29 days in leap year). (Nones on the 5th, Ides on the 13th)
      3. Martius -- 31 days (Nones on the 7th, Ides on the 15th)
      4. Aprilis -- 30 days (briefly renamed by Nero as Neroneus in 65 AD until his death) (Nones on the 5th, Ides on the 13th)
      5. Maius -- 31 days (briefly renamed by Nero as Claduis in 65 AD until his death) (Nones on the 7th, Ides on the 15th)
      6. Iunius -- 30 days (briefly renamed by Nero as Germanicus in 65 AD until his death) (Nones on the 5th, Ides on the 13th)
      7. Iulius -- 31 days (Nones on the 7th, Ides on the 15th)
      8. Augustus -- 31 days (Nones on the 5th, Ides on the 13th)
      9. September -- 30 days (briefly renamed by Caligula as Germanicus in 37 AD until his death, then back to September, then briefly renamed by Domitian as Germanicus in 84 AD until his death) (Nones on the 5th, Ides on the 13th)
      10. October -- 31 days (briefly renamed by Domitian as Domitianus in 84 AD until his death) (Nones on the 7th, Ides on the 15th)
      11. November -- 30 days (Nones on the 5th, Ides on the 13th)
      12. December -- 31 days (Nones on the 5th, Ides on the 13th)
      13. Commodus was unique in renaming all twelve months after his own adopted names (January to December): "Amazonius", "Invictus", "Felix", "Pius", "Lucius", "Aelius", "Aurelius", "Commodus", "Augustus", "Herculeus", "Romanus", and "Exsuperatorius"
    6. Sample Month Design:
      1. Ianuarius:
      2. 1. Kalandae Ianuarius
      3. 2. a.d. IV. Nonae Ianuarius
      4. 3. a.d. III. Nonae Ianuarius
      5. 4. pridie Nonae Ianuarius
      6. 5. Nonae Ianuarius
      7. 6. a,d, VIII. Idus Ianuarius
      8. etc. etc.
      9. 12. pridie Idus Ianuarius
      10. 13. Idus Ianuarius
      11. 14. a.d. XIX Kalendae Februarius
      12. etc. etc.
      13. 31. pridie Kalendae Februarius
      14. Februarius:
      15. 1. Kalandae Februarius
      1. Martius:
      2. 1. Kalandae Martius
      3. 2. a.d. VI. Nonae Martius
      4. 3. a.d. V. Nonae Martius
      5. 4. a.d. IV. Nonae Martius
      6. 5. a.d. III. Nonae Martius
      7. 6. pridie Nonae Martius
      8. 7. Nonae Martius
      9. 8. a,d, VIII. Idus Martius
      10. etc. etc.
      11. 14. pridie Idus Martius
      12. 15. Idus Martius
      13. 16. a.d. XVII Kalendae Aprilis
      14. etc. etc.
      15. 31. pridie Kalendae Aprilis
      16. Aprilis:
      17. 1. Kalandae Aprilis
    7. 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.
  2. Leap Day Rules:
    1. in order for the dates between Julius's design to line up with the Julian-Roman-1 calendar, the insertion of Leap Year Days were suspended until either of the years 4 A.D. (757 UAC) or 8 A.D. (761 UAC) depending on scholar.
    2. Since there was no more intercalary month, there was a new system of inserting a single 24 hour period 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.
    3. Julius Caesar decreed that in leap years the "6th day before Kalendae of March" should be doubled, right after VII Kal. Mart. (the seventh day before Kalendae of March) where the old intercalary month was once inserted) for religious reasons. The doubling of the 6th day before Kalendae of March is the origin of the word bissextile.
    4. Terminalia was VII Kal. Mart or Feb 23, which was the end of the first part of February. Macrobius states during the Republican Calendar II years that the old Roman year (not the civil year) began after Terminalia day ended with the Julian-Roman-Actual-1 calendar.
    5. 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.
    6. Initially, the early Julian-Roman-1 calendar had 28 days in February, but during leap years, it still had 28 days, though through a method of expanding where February 24 matches VI Kal. Mart into a 48 hour day, so physically, though not numerically, it was really a 29-day month. The Romans had the same date VI Kal twice in Leap Years. An example of that is when on the day the clocks are set back one hour, there's still 24 hours on the day numerically, but in reality, it was a 25-hour day with the 1 A.M. hour repeated twice.
    7. So here's how the intercalary 24 hours were inserted on the Julian-Roman-1 calendar. At first, the VI Kal. Mart. was expanded to 48 hours to create a biduum concept of a two-day period called Bissextile.
    8. Bissextile (not to be confused with Bissextile Day) was treated like one 48-hour day with two sunrises and two sunsets, but to explain how it was in reality on a physical scale, there were two halves of the 48-hour day that wasn't named yet.
      1. The first 24 hours of the biduum space was the intercalary day, or simply named Intercalary Day, that would later be called Bissextile Day, or (bis.) VI Kal. Mart., possibly Feb 24 Posterior, or even Bissextile Prior. It was placed right after VII Kal. Mar. For those using the Kalends month dating method, that is Leap Year Day.
      2. The second 24 hours of the biduum space was the normal VI Kal. Mar. It maps to the Julian-Countup-1 and Julian-1 calendars at Feb 25 when February was 29 days long.
    9. Leap Year Days were every four years from 8 (or 4) C.E. onwards, and backwards every four years from 1 B.C.E. proleptically.
    10. Leap Days were supposed to be inserted five days before the end of February (between Feb 23 and 24) on the Julian-Roman-1 calendar featuring the Kalends day numbering method. Although a Feb 29 is inserted at the end of February on months with days counting up from one, 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.
    11. Gradually beginning in around the 3rd century C.E. until around the 7th century C.E. I guess, the biduum concept began to disappear from future Julian-Roman-1 calendars. Around 364 C.E., the first 24 hours of Bissextile began to be regarded as Bissextile Day or (bis.) VI Kal. Mart. in many calendars if not most calendars in use.
    12. Around the Middle Ages, February 29 came to be regarded as the leap day when the Roman system of numbering days was replaced by sequential numbering, though traditionalists still regarded February 24 as the leap day even with the counting up the days of the month method.
    13. The last days of February with the leap year day looked like this:
      1. Feb 21, 22, 23, 24 Posterior, 24, 25, 26, 27, 28
      2. In counting up the days of the month method: Feb 21, 22, 23, 24, 25, 26, 27, 28, 29
      3. In early Julian calendar dating correspodence: IX Kal, VIII Kal, VII Kal, VI Kal Posterior or (bis.) VI Kal, VI Kal, V Kal, IV Kal, III Kal, pridie Kal.
      4. March 1 was Kal I.
      5. Leap Day would be the equivlant of February 24, then February 25-29 would still be the same VI-pridie Kal days.
  3. Four variations of this Julian-Roman-1 calendar
    1. Julian-1 (aka Julian-Christ-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.
    2. Julian-Kalends-1 (aka Julian-Christ-Kalends-1), days counting down to Nones, Ides and Kalends, and the year of reckoning is 1 B.C., the year Christ was conceived. This was conceived in the middle of the first millenium as it replaced the reckoning year of Rome.
    3. Julian-Roman-1 (aka Julian-Roman-Kalends-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.
    4. Julian-Countup-1 (aka Julian-Roman-Countup-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)

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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