Calendars and Reckoning · 11:06pm May 7th, 2018
Once upon a time, in the magical land of Equestria…
As has been widely commented, the mention of Celestia’s “ones-versary” in Horse Play provides a unique reference point to fix the Equestrian calendar. We now know Twilight’s school was up and running 1111 years after Celestia first raised the sun. We could question whether Pinkie Pie is a reliable source, but taken at face value it sets the scale of Equestrian history.
It’s not exactly what we expected. It suggests the later adventures of Starswirl the Bearded, the defeat of Discord, and the rise and fall of Nightmare moon all happened in little over a century. Then Celestia was twiddling her hooves for the next thousand years. I think most of us thought things were a bit more spaced out.
This episode ties in nicely with the story written in the Journal of the Two Sisters. While a valuable source for anyone wanting to study Equestrian lore, the journal has a frustrating lack of any dates. There are also no mentions of calendar months in the show, although the frequent and casual mention of ‘moons’ as a unit of time suggests there is some lunar cycle beyond the nightly raising and morning lowering of the satellite. Maybe Equestria has both a solar and a lunar calendar (I think someone suggested that as an explanation why Rainbow Dash’s birthday and the anniversary of her move to Ponyville happen on the same day in Pinkie Pride, in a way that implies this does not happen every year.)
The absence of any Equestrian calendar has encouraged plenty of fans to invent their own, often with quite elaborate features. When I wrote Time on Their Hooves I knew I would have to do my own, as that’s what the story is about. As I was more interested in the question of how ponies could measure time than thinking up fancy names for new months, and I wanted parallels with our world history, I opted for the usual twelve months, and put Year 1 [1] at Celestia and Luna’s coronation, and Luna’s exile a millennia after that. (I liked the idea that season 1 episode 1 begins in the year 2001.)
[1] Whether the Calendar should start with Year 0 or Year 1 is a question I never addressed.
Perhaps I should now go back and edit that story to be compatible with the show, although that might be complicated and I might just make a mess of it.
If the new datum provided by the onesversary creates problem for your headcanon, there are plenty of ways around this. What is an Equestrian year anyway? Is it define as 31557600 seconds? Is this fixed by whatever Celestia does with the sun? By the work shifts at the weather factory? Rainbow Dash may have failed to stop winter by sabotaging the factory, but who can say what life was like in the old days? Maybe in the early years of Equestria they just let summer drag on for moons until they got bored of it and wanted winter again. Yet when the weather factory was constructed, managers started to insist on proper schedules. Or maybe during the years of Luna’s exile, Celestia got bored waiting and decided to fast-forward the sun for a bit to bring closer the time when the stars would aid in her sister's escape?
"You gotta be kiddin' me! I can move the sun?! A ha ha! Wow! Now this is what I'm talkin' about! Ha ha! Time to play! Tuesday, Wednesday, Thursday, Friday! Day, night! Day, night! Day night! Day night! Day night! Sunrise, sunset!"
Our world may not have quite such interesting problems with chronology, but there are still plenty of quirks in our calendars to keep historians and astronomers occupied. In ancient Rome, the high priest of the pontiffs had the power to decide whether or not an extra month, the mensis intercalis, would take place, adding 27 or 28 days to the year. Used appropriately, it could keep the calendar aligned with the solar cycle, yet according to some sources, it was too easy for the officials to abuse this power to lengthen (or reduce) the time in office of their political allies (or rivals). Julius Caesar then introduced the Julian calendar of 365 days (with a leap day every four years).
This was further reformed to better sync to the solar cycle in 1582 with the Gregorian calendar, used today. The ten or more day difference between the two systems provides an interesting extra challenge to anyone studying the early modern period, as different countries adopted the new calendar at different points. For example, this means you can say Isaac Newton was born on 25 December 1642, or on 4 January 1643. Britain did not adopt the new calendar until 1752, as the early modern English didn’t like those Europeans telling them what day it should be.
When the Gregorian calendar finally did reach the British Isles, the response of the average Brit to being told that Christmas Day had suddenly moved was to decide that, in order not to offend God either way, they needed to have a period of uninterrupted drunken revelry stretching from one to the other. And that's where the Twelve Days of Christmas came from.
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Judging from Shakespeare's plays, that was pretty much the same as what they did under the old calendar, but I expect they appreciated the new justification.
We do not now the base used. The Oneversary could be hundreds of years ago or millions. I myself am partial to sexagesimal (base60).