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69
votes
10answers
28k views

Why does the United States keep using “old” date representations and imperial system, while being in the minority?

Other than the US (and a few other countries), the vast majority of countries use International System of Units (SI). Celsius temperature scale. DMY or YMD date format┬╣. 24-hour clock when written┬▓. ...
19
votes
2answers
703 views

in what form did William the Conqueror write the date of his own coronation?

This is a question about the English legal calendar as viewed by people living at the time, not as historians recorded it later. New year shifts to 1-January To the best of my understanding, the ...
17
votes
3answers
3k views

What is the reason that not all roman emperors named a month after them?

As far as I know, Julius Caesar and Augustus named the fifth and the sixth months, respectively, after themselves, but why didn't Tiberius, Caligula, Claudius, and Nero do the same while there were ...
16
votes
5answers
365 views

What was the Julian Calendar aligned to?

I understand that the Julian Calendar was introduced to align the length of the calendar to the tropical year, i.e. make the average year 365.25 days long. However, what I'm still trying to figure out ...
15
votes
1answer
496 views

What was the motivation for the Gregorian Calendar?

The Gregorian Calendar eventually replaced the Roman calendar at some point, I know this was something to do with the days not being quite accurate so specific days (I think equinox and solstice) were ...
15
votes
1answer
872 views

Why is the leap day on February 29th?

Every four years, besides some certain years, we have a leap year, where a 29th day is added to February in the Gregorian calendar, making the year 366 days long, rather than 365. This is to make up ...
14
votes
2answers
432 views

What is the earliest reliably dated event exact to the year?

How far does reliable counting of the years reach into the past: with the help of dating methods? using only primary sources?
14
votes
2answers
220 views

In the French Republican calendar: were Quintidis holidays?

I did some research on the French Republican calendar and found some contradictory information on weekly (or decadian?) holidays. Wikipedia (and most other articles I found) mention: The ...
13
votes
2answers
203 views

When was the change from kalends, ides and nones to numbers

The Romans named the days of the month by counting down to kalends, ides and nones. We use numbers counting up from one for the first day of the month. When did this change take place? I assume that ...
12
votes
6answers
2k views

Is every major culture in the same year?

In the Western world the current year is 2014, which is the number of years since the birth of the Christian messiah. Given that Christianity is not the dominant religion in every part of the world, I ...
10
votes
4answers
770 views

How come every culture on the Planet has a different calendar, yet follow the same system for a week?

I know it sounds a bit like a silly question. Every culture in the world follow a different Calendar, for instance: Christians follow a solar calendar following the birth of Jesus Christ (2014. AD ...
10
votes
2answers
3k views

Why today's Japan celebrates Western New Year but China still celebrates Chinese New Year?

Before Meiji Restoration, Japan used Chinese calendar and celebrated Chinese New Year just as China did. Nowadays, both Japan and China have adopted Western calendar. However, Japan celebrates ...
9
votes
3answers
530 views

How was the current month and day disseminated to the townspeople of Medieval Europe?

How was the current month and day disseminated to the townspeople of the Medieval Europe? I'm quite sure that personal calendars weren't a thing back then... but I could be wrong... If they had a ...
9
votes
1answer
205 views

Why did the start of the Roman consular year move?

Thus quoth wikipedia: The first day of the consular term changed several times during Roman history. It became 1 January in 153 BC. Question is: why? (And what is the source, since wiki is ...
8
votes
1answer
415 views

Who uses a pre-“Gregorian” calendar and why?

Here's a "day job" question that apparently has its roots in history. A person with one of our (overseas) suppliers declined to work this week, because it's his Christmas holiday. He's Orthodox, and ...
8
votes
1answer
609 views

How did the French take the Republican Calendar?

I've been wondering what the reactions were in France to the new Republican Calendar. When I learned about it in school, it seemed ridiculously overzealous to me, and this notion hasn't left me since. ...
8
votes
2answers
394 views

Which days in the Mayan calendar were most auspicious for performing sacrifices?

In Classic Mayan civilization, human sacrifices were performed. I've read that there were days that were more and less auspicious for sacrifices, but I haven't been able to find out which days those ...
7
votes
1answer
300 views

Which calendar to use in English for non-European countries?

When a modern historian is writing about European history in the English language, I know it is customary to use either the Julian or Gregorian calendar, whichever was in force in the time and place ...
6
votes
1answer
815 views

How did historians sync up historical dates of different cultures? [closed]

How do people know, say, that some specific event happened in China 1200 BC? Or the Mayans did something in AD 150? Back then, didn't they all use a different calendar system?
6
votes
1answer
152 views

Who is responsible for the oldest known calendar?

What is the oldest known calendar? Where exactly was it developed? Who was responsible for its creation?
6
votes
0answers
149 views

Date of the death of Socrates

Question 1: The death of Socrates is usually said to have happened in 399 BC, but I've sometimes seen a question mark after the date. Is there actually a possible uncertainty about the exact year? ...
5
votes
2answers
161 views

What holidays would be on a European-centric calendar from the 11th - 13th Centuries?

I've often come across readings that mentioned there were numerous holidays in calendars in use within the Christian Churches or Church controlled lands, with work stopping on worship days, feast days ...
5
votes
2answers
148 views

Why does the Gregorian calendar start where it does?

The way a calendar is organized is very dependent on celestial events. A month is about the length of time the moon revolves around the earth and a year is the time the earth revolves around the sun. ...
5
votes
1answer
112 views

Were the dates of saints days moved as part of the Gregorian calendar reforms?

I understand that if one were to go back in time and ask a participant at the battle of Agincourt what the date was, he would (if he knew) say that it was the 16th of October, he would also (more ...
5
votes
1answer
113 views

Who fixed new year's day as 25th March in 1155 CE

I have read that New year's day was fixed at Lady Day 25th March from 1155 until the reform in 1752, but I can't find out who fixed it and why, can anybody help? Responding to the comment by C.G. ...
4
votes
2answers
531 views

Historically, how come we have 7 days in a week? [closed]

I know jewish culture tend to like number 7. What about other cultures? Do we have 7 days in a week from bible? Why do we derive 7 days a week from jews? Why not from more prominent culture, like ...
4
votes
1answer
628 views

How is the year “753 BC” given in ancient legends about the founding of Rome?

According to tradition, the founding of Rome by the legendary figures Romulus and Remus occurred in the year "753 BC". Of course, ancient Roman scholars would not have referenced that date using the (...
4
votes
1answer
84 views

Mayan calendar coinciding with winter solstice

It appears that all anyone has been talking about is the end of the world, misinterpretations aside (at least I hope so) my understanding that this is simply the end of an age of the Mayan calendar. ...
4
votes
2answers
134 views

How was debt handled in the change over from the Julian calendar to the Gregorian?

I was reading about New Style and Old Style dates, and I thought about the deletion of dates during the transition. From Wikipedia's article on the Gregorian calendar: When the new calendar was ...
3
votes
1answer
204 views

Why does the US use MM/DD/YY?

Alternatively: why and when did others switch away from MM/DD/YY, if they ever used it? I always write out the month name to avoid ambiguity. Update: Since it came up in the comments, I'm asking ...
3
votes
1answer
93 views

When did Frankfurt am Main adopt the Gregorian Calendar?

The Gregorian Calendar was adopted in Habsburg lands in 1583. As Frankfurt am Main was a Free City within the Holy Roman Empire, it fell under direct control of the [Habsburg] Emperor. However, if I ...
3
votes
0answers
97 views

Why was the seventh day of the week in Quichua named after the sun?

In Tawantinsuyu, Incan society had a seven day week. The days could be enumerated as following: Monday: AWAKI puncha Tuesday: AWKARIK puncha Wednesday: CHILLAY puncha Thursday: KULLKA puncha ...
3
votes
2answers
74 views

Correlation between Mesoamerican and South Asian calendar systems

The Mayan and Hindu calendars both divide history into eras, and the epochs (start date) of their current eras lie extremely closely together: August 11, 3114 BCE (Mayan) vs. 18 February, 3102 BCE (...
2
votes
1answer
277 views

Why have both July and August 31 days?

Is there a reason why months alternate between 30 and 31 days? 365.24/12 = 30.23666; there are many ways to allocate the .2366 days among the months. Why was this chosen? Is there a reason why July ...
2
votes
1answer
182 views

How strong is the current theory of the beginnings of Chinese writing?

I've heard the claim that the current Chinese calendar was introduced some times around 2637 BCE by Emperor Huang Di. Apparently, written records date back to about 4,000 years ago and before that the ...
2
votes
1answer
61 views

What was considered an epoch by the Phoenicians?

The Phoenicians used a lunisolar calendar similar to the Hebrew calendar. Do we have any idea about what Phoenicians considered as an epoch for their calendar, or at least about the nature of the said ...
2
votes
0answers
83 views

Is this absolute timeline correct? [closed]

I always thought it put things into perspective if, instead of the Gregorian Calendar, we had a kind of "absolute" timeline, going all the way back to the big bang, as well as we can define it as of ...
1
vote
3answers
99 views

Where and when was the shortest calendar day in history, due to DST and calendar changes, etc?

I'm not asking about the length of daylight for the winter solstice. I'm asking about whole days that are shorter than 24 hours. For example, anywhere that observes Daylight Saving Time has one day ...
0
votes
1answer
101 views

How were years numbered on the Republican Calendar? [closed]

The French Republican Calendar was created after the revolution to remove all religious references from the calendar, but how were years numbered on it? The Gregorian Calendar (which was used before ...
0
votes
2answers
286 views

What is the earliest written date?

What is the earliest written date found? When I say "date" I primarily mean a date in the Gregorian calendar (perhaps the calendar-year is most interesting). It could also be interesting to know ...
0
votes
0answers
31 views

When did they start counting the days from 1 to 31 in Europe? [duplicate]

In history the Romans didn't count their days of a month not by adding each day extra. But instead of that they used three moments in a month, Kalendae, nonae and Idus. And from those days they ...
0
votes
0answers
16 views

When was the change from kalends, ides and nones to numbers [duplicate]

The Romans named the days of the month by counting down to kalends, ides and nones. We use numbers counting up from one for the first day of the month. When did this change take place? I assume that ...
-1
votes
1answer
134 views

Mnemonics for centures or any other longer periods, like Zodiac signs other than Chinese? [closed]

I would like to have compatible mnemonics to remember historical dates. "Compatible" means it should not be my own mnemonics, but something, related with old cultural and historical symbols, like ...
-2
votes
1answer
143 views

Why is a month so different from a year or a day? [closed]

I dont know whether this is the correct place to ask this, but I don't know anywhere else. A minute is 60 seconds, an hour 60 minutes, and a day 24 hours always. Again, a week is 7 days always. And ...