Ok so I enjoy this joke a lot too, but the actual history behind this is a bit more complicated and honestly illuminating in its wackiness.

Let's talk about Roman calendars!

So why do the 'number months' (Sept-Dec) not correspond to their numbers (7-10)? 1/
As many people know, the back four months of our calendar are effectively numbered:
September - Seventh Month
October - Eight Month
November - Ninth Month
December - Tenth Month

Except none of them are in their right numerical position. Why?

The Romans. 2/
The normal version of this story you'll hear is that this is all Julius Caesar's fault for 'adding' July, but that's not quite right, a bit of folk history.

July and August existed long before, they were called Quintilis (fifth) and Sextilis (sixth).
So what happened? At some early point, the Romans do seem to have had a ten-month calendar. Later sources (Macrobius, Plutarch) place this in the period of the legendary kings. 4/
By the point where we can observe them (centuries before Caesar) the Romans are, however, operating a twelve month calendar. Our sources (Plut. Numa 18; Liv. 1.19.6-7) credit the legendary king Numa (r. LOL, not a real person or 715-672) with the 12 month calendar. 5/
Numa isn't really a historical figure, so the best we can say from this is that the shift to a twelve month calendar happened so far in the past that by the historical period the Romans only dimly remembered it. 6/
That newer 12-month calendar has some wackiness though, because it's trying to harmonize the lunar and solar calendars and they don't actually fit, so the standard year on the calendar is 355 days, which is notably not 365 days. 7/
The patchwork fixes to this was to add an 'intercalary month' - basically a bonus month - every other year at the end of the year to 'reset' the system. Put a pin in that because we'll come back to it.

But what about the names of the months? 8/
The names of months are, except Quintilis and Sextilis, the same, but for a slight difference in the order, see if you can spot it:
Martius -> Aprilis -> Maius -> Iunius -> Quintilis -> Sextilis -> September -> October -> November -> December -> Ianuarius -> Februarius. 9/
That's right!

The year starts in March! That intercalary month, placed at the end of the year, happens at the end of *February*! 10/
And this makes a lot of sense. March - the month of Mars - marked the beginning of the Roman religious calendar and the start of the campaigning season, with lots of rituals preparing for an army to be raised. It makes sense to start the year there. 11/
And with March coming first, all of the 'number months' fall neatly on their numbers before January and February (likely the two months added to get to 12 way back when) come last as months 11 and 12. 12/
So why do we start the year with January? The Romans again, but *still* not Julius Caesar.

In this case our sources tell us. Livy reports that in 153 the consuls first began to enter office (and thus start the year) in January. 13/
Or more correctly, the Periochae, a summary of Livy's history which gives us some insight into books that are lost (such as Liv. 47, which covered 153) reports that this happened "because of a rebellion in Spain." (Liv. Per. 47.13 🤷‍♂️ 14/
Still, that's pretty reliable: Livy will have been able to confirm this detail and get it right. But why?

Rome's consuls, the two highest officials, had the job of raising and commanding Rome's main armies. So coming into office in March...15/
...and then immediately enrolling those armies initially made a lot of sense. But the tight timing of all of that may have become a problem as Rome's empire grew and the Romans found themselves embroiled in major wars far afield. 16/
Bringing the consuls in two months early would give them time to handle domestic affairs before the campaigning season before the draft in March and still have time to get to armies already in the field in places like Spain before the fighting season began in earnest. 17/
But the Roman calendar was religious, as was Roman politics. The calendar was kept by the Pontifex Maximus, while consuls were ritually inaugerated ('augered in' where augury is 'divining the will of the gods from the flights of birds) for the calendar year. 18/
So moving the date the consuls entered office meant shifting the entire calendar, taking the two last months and making them the two first months, throwing off the position of all of the number-months.

Alas, the Periochae does not tell us who specifically was responsible. 19/
So what did Caesar do with the calendar? Well, the thing is, the Roman calendar here is still a mess - it requires the Pontifex Maximus be very active in setting intercalary months of the right length or the whole thing drifts off of the correct seasons. 20/
And that matters a lot - these are agricultural societies where seasonal cycles are very important.

In the chaos of the first century, those adjustments had been repeatedly not happening. It didn't help that the Pont. Max spent the 50s in Gaul, not in Rome. 21/
That Pont. Max' name was Julius Caesar, of course.

By the mid-40s BC, the calendar was almost a hundred days off. Finally in 46, Julius Caesar takes some time out of his busy schedule of Doing Wars to actually be in Rome to fix the calendar. You know, his job as Pont. Max. 22/ Image
Caesar brings in the best astronomers and mathematicians - from Egypt, where the study of those things was more advanced (Plin. NH. 18) - tweaking the lengths of all of the months to get the year to the 365 days(ish) of the solar calendar. 23/
Then, to reset the start of the year to the right spot, he extended 46 BC to 445 days. Since we still use this calendar system (in many but not all countries), 46BC remains the longest year.

Wikipedia's note that this did not change planetary orbits is hilarious. 24/ Image
Quintilis was only renamed 'July' in 44 after Caesar was dead (in March, you may recall), in his honor. Sextilis was renamed 'August' in 8BC, giving us the months as we have them now.


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More from @BretDevereaux

Dec 1
Every so often I marvel at what a killer idea Hollow Knight's City of Tears is - a forlorn city carved underneath an underground lake such that it is always raining - and wish I had thought of it for an RPG setting.

Also the music totally sells it:
Always really struck by the use of music in games to sell a feeling about a place. My go-to example is Streets of Whiterun () which does a lot of the heavy lifting in getting the player to form an emotional attachment to Whiterun in Skyrim.
It seems like when a player needs to feel a place - especially if the feeling is something other than fear or tension - soundtracks tend to carry a lot of that narrative weight.

If it needs to feel like home, e.g. while we're here, Besaid Island from FFX:
Read 9 tweets
Nov 28
Alright, time for some history twitter, let's talk about that most exciting of topics, ancient land tenure and ownership! ::airhorn noises::

(Why yes, I am like this stone-cold sober, why do you ask?)

Because the ownership of land often worked a bit differently. 1/
In most modern societies, we tend to assume an owner-operator default to land ownership: a farm is owned by a farmer who farms it, perhaps also with employees. Our actual land tenure systems are way more complicated than this, but this is what we assume. 2/
By contrast pre-modern agrarian societies both absolutely had the idea of landed property, but also had somewhat 'fuzzier' understandings of it, with blurrier lines between public and private lands and ownership. 3/
Read 40 tweets
Nov 18
When I was a grad student, I wondered why most of the best scholarship on Roman equipment/material culture was done in Europe and much less in the USA. I think museum access is a big factor, but also so much is published in small-run books that are very hard to get over here.
I've never had anything I couldn't get - being affiliated with UNC means having the Davis Library's ILB team (♥️ @UNCLibrary ) and they are magicians.

But in terms of research time, there's a big difference between "we have it" and "we need a week or two to go get it."
And of course time is the big research resource. You can solve some of this with parallelism - pause one topic, start up another - but at some point it all eats up time and that imposes costs in terms of research scope or comprehensiveness or just what people want to look into.
Read 6 tweets
Nov 17
One of the things in visual representations of the past, especially a 'fantastic' past (e.g. fantasy medieval Europe) is the tendency to skip over the period when mail was the dominant heavy armor, from roughly the second century BC to the 13th century AD.

So let's talk mail. 1/
Part of this is noticing that House of the Dragon, visually, has decided that even though its events take place 200 years earlier than GoT, the dominant armor is plate, not mail, but you also see this in Tolkien adaptations; Book!LotR is all mail, screen!LOTR is mostly plate. 2/
So this is a mail appreciation thread. First, terminology: chainmail or worse ringmail are both modern terms and scholars thus tend to avoid them, preferring the medieval 'mail.' Roman mail armor tends to get called 'lorica hamata' which *may* have been a proper ancient term. 3/
Read 32 tweets
Nov 16
I understand the desire to see Putin's war of aggression in Ukraine fail; I do too. But I think glee at a potential escalation involving Poland/NATO is short-sighted. It's that 'emotive strategy' I talked about.

Let Plato's charioteer drive the chariot, not the horses.
Anyway, I talk about common strategic errors including the sin of emotive strategy here: acoup.blog/2020/06/19/col…
It is one of the three great strategic sins (I am open to there being more, but in my own study, these are the three I most often detect):
1) Emotive Strategy (vibes instead of plans)
2) Operations usurping strategy
3) Failure to update the strategy to changing conditions.
Read 8 tweets
Nov 15
Looking at the FTX implosion and the increasing likelihood of Bankman-Fried ending up awkwardly in a courtroom and feeling pretty good about this February fireside where I talked about the state preference for 'meatspace' strategies: acoup.blog/2022/02/04/fir…
Admittedly I do not fully understand all of the fancy technical details, but I *do* understand some things about states - they are jealous creatures and apt to suspend their self-imposed rules if their power is sufficiently threatened.
There's a reason the clever criminals - be they crooked politicians or mob bosses - don't try to fight the state, but instead aim for some degree of state-capture.

Fortunately it looks like the air is going out of the crypto-balloon well before they could manage that.
Read 5 tweets

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