# Date format I've not run across before **URL:** \ **Category:** Factual Questions\ **Created:** [January 14, 2016, 3:16am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105 "2016-01-14T03:16:20Z")\ **Posts on this page:** 19\ **Page:** 1
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [January 14, 2016, 3:16am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/1 "2016-01-14T03:16:20Z")
In doing some genealogical research, I’ve found dates recorded in a way I’ve not seen before, and I wanted to get some input about it, hopefully from someone who is familiar with it. The format is as follows: 15 : 3 m : 1641 I quickly grasp in looking at it that the obvious “modern translation” would be 3/15/1641. But other sources which give the same information (in this case, a birthdate) say it should be interpreted as 5/15/1641. Combined with other examples I have which all correlate, I’ve figured out that they are counting months starting with March, because all the dates have been consistently interpreted as 2 months beyond what I would normally read it as. So far, I’m wrapping my head around this pretty well. Here’s where it fails me: I have a date which is, for example, 25 : 12 m : 1641. So that would be 2/25/1641. But then my head says, "no, if you’re counting starting from March of 1641, that would be 2/25/1642. And then I give up, because why would you come up with a system like that? If you know what year it is, and it’s the same year system we use today, why aren’t you starting and ending your years on the same months we do today? Am I really ready to accept a calendar that starts 1641 with 11 m, then 12 m, then 1 m through 10 m? Help? ETA: [Google Books link](https://books.google.com/books?id=PWoMAAAAYAAJ&pg=PA216&lpg=PA216&dq=7+:+11+m+:+1641&source=bl&ots=2VTPOJQgf7&sig=dsJsJbd-bOv4TUSf-j7Um7chF_Y&hl=en&sa=X&ved=0ahUKEwiOrrSTrKjKAhWCSSYKHdOHCUQQ6AEIHDAA#v=onepage&q=7%20%3A%2011%20m%20%3A%201641&f=false) to page in historic book with examples aplenty. And to amp up the maddeningness of it all, apparently, at some point they just stopped and started using a modern format. ---
**Author:** ![UDS](https://avatars.discourse-cdn.com/v4/letter/u/ecae2f/32.png) [@UDS](https://boards.straightdope.com/u/UDS)\ **Post date:** [January 14, 2016, 3:58am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/2 "2016-01-14T03:58:29Z")
The cycle of months in the year, and the sequence of years, evolved separately and are in principle unrelated. We get the cycle of months from the Romans, as no doubt you know. (Well, OK, the idea of a twelve-month cycle is older than that, but the names we use come from the Romans.) The Romans, as you have again probably heard, usually identified a year according to who were the consuls for that year (E.g. “I was born in the consulship of Caesar and Bibulus”). But they also counted from the foundation of the City. Much later Christians replaced this with a system of numbering years from the (supposed) date of the incarnation of Christ is much later. But when does the year turn? The whole point about a cycle (like the cycle of months) is that you can start at any point and you’ll come back to that point. So, if you’re looking for a “first day of the year” candidate, any day is as good as any other day. The Romans took the view that the year turned on 1 January - it was the winter solstice, or close enough, and it was also the day on which newly-elected consuls entered into office. But when the Christians started to use their incarnation-based dating system, there was nothing special about 1 January. Since the Annunciation - the point at which Christ is supposed to have been conceived in the Virgin - was celebrated on 25 March, that seemed a rational date for the turn of the year. Hence for a time the first day of the year, Christian-style, was 25 March. Under this system 24 March 1342 would be followed by 25 March 1343. This, of course, made for endless confusion, especially when the Renaissance came along and brought with it a renewed interest in, and respect for, the pre-Christian classical world. For a time a date might be given as, e.g. “15 February 1642/3”, meaning it’s 1642 if you consider the year to start on 25 March, but 1643 if you consider the year to start on 1 January. (You’d only find this format for dates between 1 January and 24 March.) I suspect what you are encountering here is something similar. If you’re counting your year as starting on 25 March, then the date 11 months after 25 March 1641 is 25 February 1641 - it won’t turn to 1642 for another month. In time this gets replaced with 15 February 1641/2, and then in further time with 25 February 1642. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [January 14, 2016, 4:16am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/3 "2016-01-14T04:16:54Z")
I will note that if March is considered the first month of the year, then the names of September, October, November, and December (from Latin for seventh, eighth, ninth, and tenth, respectively) make sense. I’m sorry I don’t know more about the subject, but I hope this will yield some helpful insight. ---
**Author:** ![Nava](https://avatars.discourse-cdn.com/v4/letter/n/da6949/32.png) [@Nava](https://boards.straightdope.com/u/Nava)\ **Post date:** [January 14, 2016, 4:21am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/4 "2016-01-14T04:21:12Z")
Those names are from when the Romans used a ten month calendar, before finally giving up on having a ton of “loose days” not connected to any month that they just tossed in as needed. The two additional months are July and August. January (from Janus, god of doors, gateways and big changes not assigned to anybody else) was their first month. ---
**Author:** ![RadicalPi](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/radicalpi/32/9806_2.png) [@RadicalPi](https://boards.straightdope.com/u/RadicalPi)\ **Post date:** [January 14, 2016, 4:33am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/5 "2016-01-14T04:33:24Z")
> [@Nava](#): > > Those names are from when the Romans used a ten month calendar, before finally giving up on having a ton of “loose days” not connected to any month that they just tossed in as needed. The two additional months are July and August. The new months were the winter months of January and February. July and August are just renamed versions of preexisting Quintilis et Sextilis, which mean “fifth” and “sixth.” ---
**Author:** ![Wendell\_Wagner](https://avatars.discourse-cdn.com/v4/letter/w/8491ac/32.png) [@Wendell\_Wagner](https://boards.straightdope.com/u/Wendell_Wagner)\ **Post date:** [January 14, 2016, 11:02am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/6 "2016-01-14T11:02:41Z")
There was no consistency in when the calendar year started: > **[Why Does the New Year Start on January 1?](https://www.mentalfloss.com/article/29611/why-does-new-year-start-january-1)** > > Our current calendar all goes back to the Roman god Janus. Who, way back when, was the god of doors and gates and had two faces—one looking forward and one looking back. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [January 14, 2016, 3:52pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/7 "2016-01-14T15:52:42Z")
> [@KneadToKnow](#): > > … > The format is as follows: > > 15 : 3 m : 1641 > > I quickly grasp in looking at it that the obvious “modern translation” would be 3/15/1641. But other sources which give the same information (in this case, a birthdate) say it should be interpreted as 5/15/1641. … I like how in a discussion of confusing date formats the OP decides the “modern format” is an ambiguous one currently used in only a few backwards countries. A sizeable number of Dopers will tell you that where they live “3/15/1641” cannot be a valid date as there is no 15th month of any year. ---
**Author:** ![APB](https://avatars.discourse-cdn.com/v4/letter/a/8e8cbc/32.png) [@APB](https://boards.straightdope.com/u/APB)\ **Post date:** [January 14, 2016, 4:56pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/8 "2016-01-14T16:56:11Z")
It is worth remembering that the name of month was usually spelt out in full or abbreviated so there would normally be no ambiguity as to which month was meant. But what the OP is seeing are examples of what is often called Quaker dating. That’s because some people avoided using the names of the months for religious reasons, on the grounds that some of them derived from the names of pagan deities. Although particularly associated with Quakers, its use predated them. In the case of Massachusetts, dates were given in that form in [some of its official records](https://archive.org/stream/recordsofgoverno01mass#page/176/mode/2up) from as early as the mid-1630s. And, yes, it can be really annoying. But that’s Puritans for you. ---
**Author:** ![MikeS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MikeS](https://boards.straightdope.com/u/MikeS)\ **Post date:** [January 14, 2016, 7:56pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/9 "2016-01-14T19:56:38Z")
> [@KneadToKnow](#): > > Here’s where it fails me: I have a date which is, for example, 25 : 12 m : 1641. So that would be 2/25/1641. > > But then my head says, "no, if you’re counting starting from March of 1641, that would be 2/25/1642. > > And then I give up, because why would you come up with a system like that? If you know what year it is, and it’s the same year system we use today, why aren’t you starting and ending your years on the same months we do today? Am I really ready to accept a calendar that starts 1641 with 11 m, then 12 m, then 1 m through 10 m? The problem you seem to be having is that the span of time that counts as “1641” in the Quaker dating system is different from the span of time called “1641” under the currently accepted format. Here’s how the months would line up: ```auto Modern style Quaker style December 1640 10 m: 1640 January 1641 11 m: 1640 February 1641 12 m: 1640 March 1641 1 m: 1641 (more or less; see below) April 1641 2 m: 1641 May 1641 3 m: 1641 June 1641 4 m: 1641 July 1641 5 m: 1641 August 1641 6 m: 1641 September 1641 7 m: 1641 October 1641 8 m: 1641 November 1641 9 m: 1641 December 1641 10 m: 1641 January 1642 11 m: 1641 February 1642 12 m: 1641 March 1642 1 m: 1642 ``` Each system is nice and orderly within itself; but the spans of time that each system calls a calendar year are out of phase with each other. You may or may not have found [this page](http://www.swarthmore.edu/friends-historical-library/quaker-calendar), which explains the system about as well as it can be; in particular, it points out that dates in January and February were often “double-dated” because people knew that there were different conventions about the year started. So a date in January 1642 would be written as occurring in January 1641/2. So the system makes sense to me, more or less. Where my mind rebels is the fact that 24:1m:1640 would be followed by 25:1m:1641, since the first day of the year was March 25. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [January 14, 2016, 11:01pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/10 "2016-01-14T23:01:54Z")
I remember seeing grave stones on the floor of some English cathedrals and churches for babies that died not long after birth, and there was the same issue (from the 1600’s I believe). A child would be born, say, in Oct. 1661 and died February, 1661. But in this case, the date was spelled out the usual way. ---
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [January 15, 2016, 12:07pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/11 "2016-01-15T12:07:35Z")
Thanks, everyone, for the input! > [@LSLGuy](#): > > I like how in a discussion of confusing date formats the OP decides the “modern format” is an ambiguous one currently used in only a few backwards countries. > > A sizeable number of Dopers will tell you that where they live “3/15/1641” cannot be a valid date as there is no 15th month of any year. Well, I guess scare quotes just don’t say as much as they used to. ---
**Author:** ![SmartAlecCat](https://avatars.discourse-cdn.com/v4/letter/s/67e7ee/32.png) [@SmartAlecCat](https://boards.straightdope.com/u/SmartAlecCat)\ **Post date:** [January 15, 2016, 1:35pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/12 "2016-01-15T13:35:27Z")
> [@LSLGuy](#): > > I like how in a discussion of confusing date formats the OP decides the “modern format” is an ambiguous one currently used in only a few backwards countries. > > A sizeable number of Dopers will tell you that where they live “3/15/1641” cannot be a valid date as there is no 15th month of any year. There is _ **one** _ modern format: [ISO 8601](https://xkcd.com/1179/) All others should now be discouraged. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [January 15, 2016, 2:24pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/13 "2016-01-15T14:24:20Z")
> [@Gary\_T](#): > > I will note that if March is considered the first month of the year, then the names of September, October, November, and December (from Latin for seventh, eighth, ninth, and tenth, respectively) make sense. I’m sorry I don’t know more about the subject, but I hope this will yield some helpful insight. The change to the start of the year was a papal thing, and quakers may well have objected to papal things. Also they may have avoided names for months, since a name like “November” is perhaps confusing… does it mean Ninth month, or 11th ? Back then, they all knew latin… So you see, the quaker avoidance of names of months probably wasn’t so much to avoid “pagan” names , but rather to avoid confusion, as they considered it very important to keep proper recods. If you are going to tortue someone to death before they confess, then you’d better be sure about what date you did it on … Also the names of months and days of week can be confusing when read by speakers of different languages… the name for the 2nd day of the week in one language sounds like the name of a different day in another… back before spelling was a fixed thing… back before dictionaries … ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [January 15, 2016, 3:31pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/14 "2016-01-15T15:31:53Z")
> [@LSLGuy](#): > > I like how in a discussion of confusing date formats the OP decides the “modern format” is an ambiguous one currently used in only a few backwards countries. > > A sizeable number of Dopers will tell you that where they live “3/15/1641” cannot be a valid date as there is no 15th month of any year. Microsoft will tell you that Canada’s standard is dd/mm/yyyy; but I don’t know of anyone outside of a few government forms and departments that actually uses that. Most people use the logical mm/dd/yy (or yyyy) and nowadays some use yyyy-mm-dd which sorts more easily. And then, many programs written in the USA cannot handle different date formats, so I have to change all the regional settings in Windows workstations to USA or manually change all relevant formats. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [January 15, 2016, 4:11pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/15 "2016-01-15T16:11:02Z")
The fact you could use the term “logical” to apply to mm/dd/yy gives me pause. I’ll certainly buy “familiar”, at least in the US. But logical is the one thing that format ain’t. The benighted idiocy of any current-production software that isn’t fully international format aware & compatible is appalling. The marketplace ought to be just saying “no” often enough that that garbage would fade from the scene. You do raise an interesting challenge though. If a country’s official format is one thing, but many people within that country insist on using a different format, what is software to do? Especially for ambiguous formats like mm/dd and dd/mm. No matter which way they accept or display the data somebody will misunderstand. Not to mention all the opportunities for inter-system buffoonery whenever the data is transmitted in display format. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [January 15, 2016, 6:25pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/16 "2016-01-15T18:25:33Z")
I assume “logical” applies because mm/dd/yy is simply a translation of the English language idiom where full dates are spoken as “April 22nd, 1992”. Occasionally the more formal sounding “22nd of April 1992” might be spoken, but to North Americans it sounds somewhat awkard and pretentious (IMHO). The problem I find is that a lot of programs are written for the local American market - and Canada being very similar and adjacent, businesses in Canada buy those programs too. Then, they find these quirks and work around them. The company writing the software has not great incentive to change unless they expand even further afield, which would probably necessitate language translation etc. too. So Canada gets to be a test case for many software companies. (Canada is 10% of US sized market - and if you subtract approx. 1/5 of Canada is French, even smaller.) ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [January 15, 2016, 10:12pm UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/17 "2016-01-15T22:12:28Z")
> [@md2000](#): > > I assume “logical” applies because mm/dd/yy is simply a translation of the English language idiom where full dates are spoken as “April 22nd, 1992”. Occasionally the more formal sounding “22nd of April 1992” might be spoken, but to North Americans it sounds somewhat awkard and pretentious (IMHO). Yes, I occasionally have to explain to people here that the reason Americans use the bizarre month-day-year format for writing dates is because that’s the way it’s spoken in the USA. Over here too, dates are spelled the way they are spoken: 16th January, Two Thousand and Sixteen. ---
**Author:** ![MikeS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MikeS](https://boards.straightdope.com/u/MikeS)\ **Post date:** [January 16, 2016, 3:44am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/18 "2016-01-16T03:44:19Z")
> [@Isilder](#): > > So you see, the quaker avoidance of names of months probably wasn’t so much to avoid “pagan” names , but rather to avoid confusion, as they considered it very important to keep proper recods. If you are going to tortue someone to death before they confess, then you’d better be sure about what date you did it on … I’d never heard that the Quakers were responsible for things like the witch trials and religious persecution; in fact, I’d always heard that the Puritan establishment persecuted the Quakers instead rather than the other way around. Can you elaborate on what you were referring to here? ---
**Author:** ![RadicalPi](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/radicalpi/32/9806_2.png) [@RadicalPi](https://boards.straightdope.com/u/RadicalPi)\ **Post date:** [January 16, 2016, 5:53am UTC](https://boards.straightdope.com/t/date-format-ive-not-run-across-before/743105/19 "2016-01-16T05:53:11Z")
> [@SmartAlecCat](#): > > There is _ **one** _ modern format: > > [ISO 8601](https://xkcd.com/1179/) > > All others should now be discouraged. I see your [xkcd: ISO 8601](https://xkcd.com/1179), and raise you [xkcd: Standards](https://xkcd.com/927).