Calendar (Roman realm)

the origin of the old Roman calendar is clarified, it however by the Greeks was probably taken over not surely.

The tradition attributed the calendar Romulus, to the legendary founder of the city Rome.

In the early period that Roman republic the years were not counted, but were not designated after the governing consuls. Since that 4. pre-Christian century was a counting of the inauguration of the Jupitertempels in the year 507 v. Chr. usually. The years became only later „by the establishmentthe city Rome on “( urbe condita, A. and. C.) in the year 753 v. Chr. counted. In the Roman empire the years additionally still became by anno Diocletiani (A. D.) counted; this abbreviation is identical to since 525 n.Chr. common anno Domini (also A. D.), and may not be confounded.

In its oldest form the Roman calendar a lunar calendar was soon thereafter extended and finally to 12 months with 10 months, that by after Julius the Cäsar designated Julian calendar one replaced.

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the oldest calendar

the original calendar system was a rudimentary combination one astronomically at the sun of oriented lunar calendar:
The year began at the Tagundnachtgleiche in spring and took originally 10 months: Martius (31 days), Aprilis (30 days), Maius (31 days), Junius (30 days), Quintilis (31 days), Sextilis (30 days), September (30Days), October (31 days), November (30 days) and December (30 days). The year had thus 304 days; the 61 missing days were tacitly supplemented in the winter, so that the field order took place again to beginning of spring in the Martius (March). (After Ovids Fasti)

From this calendar also the religious holidays deduce themselves Kalenden, Nonen, Iden and Terminalien , as is described in the section „the days in the month “.

calendar reform

already around the year 713 v. Chr.the problem of the missing days was concerned, the tradition after by Numa Pompilius, legendary second of the seven kings of Rome. However it is considered as more probable that the fifth king, Lucius Tarquinius Priscus, was responsible for this reform.

A Lunisolarkalender was designed, which covers a complete lunar year with one switching month:

  • The six months with 30 days each were shortened on 29 days, and at the year end the Ianuarius (after the God Ianus ) became with 29 days andthe Februarius (after the cleaning celebration Februa at the year end) with 28 days attached. Thus one year of 355 days resulted.
  • The missing 10 days became balanced by one switching month, Mercedinus (Intercalaris). The Mercedinus, with one duration of 27 or 28Days, each second year was inserted. In these years February was shortened on 23 days, on which then the Mercedinus followed.

With an alternating duration of 28 and/or. 27 days was the length of four following each other years thereby by 355,378, 355 and 377 days given. Altogether this 1465 days are contained, of four more than four tropical years.

This very unmanageably seeming construction should guarantee the attention of the religious holidays, which referred to the original moon calendar.

Under thosesurplus four days shifted in the course of the time the seasons. Beginning 6. Jh. v. Chr.first corrections were accomplished. The further accumulating shifts became as required “good in irregular distances by further corrections more or less „adapted.

Also the beginning of the year, originally at the 1. March, became for the year 153 v. Chr. on the 1. January, which shifted beginning of office of the consuls. Thus also the counting months lost (Septembers, as much as seventh, October, which respects,November, ninth, Decembers, tenth) their appropriate positions.

the Julian calendar

the disorder of the calendar arranged finally Julius Cäsar, probably after inspiration of Acoreus to accomplish a fundamental reform and so later afterit designated Julian calendar - a genuine solar calendar - to introduce. The calendar was sketched by the brightistic astronomer Sosigenes in Alexandria. The 12 months have nearly all the today still common number on days, only the Sextilis became with itsRenaming in August by one day extends, which was taken to February. The standard year had thereby 365 days. Each fourth year became an additional day after that 24. February inserted (in the first years inadvertently somewhat more frequently).

This calendar becameat the 1. January 45 v. Chr. introduced. There the Roman calendar at this time by 67 days of intended beginning of spring deviated and the year 46 v. Chr. one leap year was, had this last year of the Roman calendar 445 days (annus confusionisVerworrenes year “).

The month Quintilis was renamed in the following year after Julius Cäsar in Julius (Lex Antonia de mense Quintili („over the month Quintilis “) of the consul Marcus Antonius). The Sextilis became late emperor Augustusin honours to the Augustus. When the senate suggested likewise renaming September to his honours Tiberius with the question rejected, which then with the three tenth Caesar was.

the days in the month

the Roman calendar knewnone „going through “week, as it is usual today. Likewise the days were not sequentially counted in the month.

Three days within each monthly were particularly excellent:

in the months March, May, July and Octobers were the Nonae on the sieved monthly day and the Iden to 15. Day. All other months had the Nonae on fifth and the Iden to 13. Day. The originalCorrespondence of these days with special Mondphasen (Kalendae at the Neumond, Nonae at the increasing Halbmond, Iden at the full moon) was lost fast. ( The Iden is of „the Iden March “, at which Brutus Julius Cäsar murderedis, admits).

All other days were represented with reference to these firm data, counted always backwards by the next fixed date, whereby the output day took in account. It was thus for example the 15. May „the Idus of May “, the 7. Maywas „the Nonae of May “. The 5. May was thus (inclusive daily counting) „three days before the Nonae of May “, the 10. May was „six days before the May Idus “, the 20. May was „13 days before the Kalendae of June“. The day directly before the fixed date was called „Pridie “.

The counting of the days for the months March, May, July and October was thus for example:

Day Roman
1 kalendae
2 VI
3 V
4 IV
6 pridie
7 nonae
Day Roman
10 VI
11 V
12 IV
13 III
14 pridie
15 idus
Day Roman
17 XVI
18 XV
19 XIV
21 XII
22 XI
23 X
24 IX
Day Roman
26 VII
27 VI
28 V
29 IV
30 III
of 31 pridie

calendars in our modern, Roman for the conversion, gives it some simple rules of thumb:

Data before the Nonen will lie in normal months of5 + 1 taken off, taken July and October off (MOMJUL) in the months March, May, from 7 + 1, there the Nonen on the 5. or 7. a monthly to fall can.

Data before the Iden will lie from 13+ 1 taken off, in the months March, May, July and October (MOMJUL) of 15 + 1, there evenly the Iden on the 13. or 15. to fall can.

Data before the Kalenden (1. each monthly) become of around 2 increasedDaily number of our monthly taken off.

Example: Our 21. April is according to Roman calculation: 30 days of April + 2= 32 days - 21 = 11 days before the Kalenden of May

see also

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