What is the most recent day where nothing is known to have happened? Most recent month? Year?

Aha. That’s the missing piece of information I needed.

Diaries might push things back some, but I suspect not by very much. With single-digit literacy rates, the number of diarists must have been only a small fraction of what there are now, and as I understand the OP, only surviving diaries would count. And those diaries that both existed and were preserved are probably weighted heavily towards important people, whose significant dates are largely already part of history.

I mean, yeah, you will have diary entries (even from Important People) consisting of things like “I heard a funny joke today”, or “My cat did the cutest belly-flop this morning”, or whatever. Those aren’t relevant for history, but still count for this thread. But there were probably also a lot of diarists who only bothered to make an entry at all for the big important things.

One problem is that, “My cat did the cutest belly-flop this morning”, where it exists was probably undated prior to the 1000s.

My views are evolving. Diaries with daily chronological dates only started in the 1000s. I gather there weren’t many of them during medieval times. (In Europe, most early ones date from the 1500s) I am thinking that the first month should be closer to the Dark Ages, with the first day sometime before 1540.

The Japanese classic The Pillow Book, " a book of observations and musings recorded by Sei Shōnagon during her time as court lady to Empress Consort Teishi in Heian-period Japan", dates from the 990s to 1002. As noted above, the first diary written in date form is from the Near East in the 1000s. English Parish records date from September 1538. I would (tentatively) place the most recent day where nothing is known to have happened as sometime between 900 and 1540, and the most recent month as sometime during the medieval period, perhaps 476 to 1296.Those are wide bounds, though the truth may very well may be outside them.

Perhaps related: There’s a book about December 28, 1986, a day chosen randomly, and the author found out about all sorts of things that happened that day.
Maybe there can’t be a day when nothing happens.

The Anglo-Saxon Chronicles started in the late 9th century, as annals of historical events from the 5th/6th centuries. As (by modern standards) brief summary entries by year, they obviously have by omission plenty of “nothing worth recording” days.

I hope we can get this question resolved soon, so we can get the plaque ordered in time for the anniversary.

I can see the plaque in the opening shot of a movie:

“On this day nothing happened. Somewhere, in some year.”

[Cue ominous music]

Nice find. Project Gutenberg has a translation. Here’s the entry for 800AD in its entirety:

A.D. 800. This year was the moon eclipsed, at eight in the evening, on the seventeenth day before the calends of February; and soon after died King Bertric and Alderman Worr. Egbert succeeded to the West-Saxon kingdom; and the same day Ethelmund, alderman of the Wiccians, rode over the Thames at Kempsford; where he was met by Alderman Woxtan, with the men of Wiltshire, and a terrible conflict ensued, in which both the commanders were slain, but the men of Wiltshire obtained the victory.

And here is 904’s entry:

A.D. 904. This year came Ethelwald hither over sea with all the fleet that he could get, and he was submitted to in Essex. This year the moon was eclipsed.

So eclipses were a big deal, and sometimes even allowed for daily dating. But I guess paper was expensive so entries are short and the great majority of months during the year aren’t specified. Later entries were somewhat longer. For example the 1013 entry has 528 words. It covers the invasion of King Sweyn of Denmark sometime, “Before the month of August”.

That sounds to me like not very meticulous record-keeping, because there’s always at least one and usually two lunar eclipses per year, and each one is visible from over half of the planet. It might be notable when in the year the moon was eclipsed, but an entry of just “This year the moon was eclipsed” says almost nothing.

It was special because they could see a moon eclipsed… the lack of clouds.

Monty Python tells us about a day on which nothing happens. https://www.youtube.com/watch?v=qf7rntVimhw

Parliament granted city of london right to raise a militia in june 1650. this would free up
14000 londoners to assemble in Yorkshire in August, and cromwells army shifted to Worsecester to intercept royalist scots… 3rd civil war and the scots fled west to Worcester, where the last battle of the civil war(s) occurred. So there was a lot of stuff going on. Important people from the halls of trades were being installed as alderman with the intent that they would then act as recruiters, to fill the militia with workers from their trade… the trade halls were officials which had records of apprentices and employees of the various shops … workers quite eligible to join the militia or army.

Activity in the months around June -September 1650 would contribute to the assembly who would convict and execute Charles 1. A militia protecting london … alderman were pressed ganged into service. … they were fined or sent to prison for not doing Cromwells bidding.

Erm… He’d been executed over a year before.

While we’re pushing back in time documentation of specific events on specific days, I offer this ostracon from the British Museum, which records absences with (often pretty lame) excuses of labourers. It is dated at Year 40 of Ramses II’s reign, which is about 1250-1240 BCE, depending on your source. It gets down to specific days when people like Penduauu were clearly having a bludge.

Inscription translation: Year 40
Penduauu: month 1 of Spring, day 14 (DRINKING WITH KHONSU) *
Hornefer: month 2 of Winter, day 13 (WITH HIS BOSS), day 14 (WITH HIS BOSS), day 15 (WITH HIS BOSS), month 2 of Winter (WITH HIS BOSS), day 16 (WITH HIS BOSS), day 17(WITH HIS BOSS), day 23 (WITH HIS BOSS)…. month … of Summer, …. (…) *
Hornefer: month 2 of Summer, day 10 (ILL) *
Sawadjyt: month 3 of Spring, day 23 (WITH HIS BOSS), day 24(WITH HIS BOSS), month 4 of Spring, day 16 (HIS DAUGHTER WAS BLEEDING), month 1 of Winter, day 14 (OFFERING TO THE GOD), month 1 of Winter, day 15 (DITTO), month 1 of Winter, day 24 (LIBATING TO HIS FATHER), day 25 (DITTO), day 26(?) (DITTO), day 28(?) (WITH HIS BOSS) *
and lots more

Neat find, Banksiaman, lots of anecdotes about particular days c 1250. OP pitches a question where the journey beats the destination.

I think I can roll the daily date back before 1400. The Veritable Records of the Joseon Dynasty are national treasures of South Korea and contain the longest continual documentation of a single dynasty in the world. They cover 1392-1865 and contain daily entries. They are digitized in Korean; they hope to complete an English translation by 2033. There are 1,893 volumes in all.

I’m rolling the most recent day back to 1392 at the latest, though I can’t be certain that the Veritable Records have surviving entries for every single day.

Current guesstimates:
Most recent mystery day: sometime between 900 and 1392.

The latest mystery month was probably before 1296, due to Lady Nigo’s diary/autobiography written in 1307 and covering 1271-1306. Lady Nigo was a nobelwoman, poet, author, and concubine of Emperor Go-Fukakusa of Japan. Towazugatari (“An Unasked-For Tale”), a 5 volume work, “Is considered one of the greatest works of Japanese literature, as well being a rare account of events not typically recorded in premodern Japanese literary works, such as sexual coercion.”

Then again, I’d like to conduct a 2nd bisect exercise for the 1300s. There’s a dearth of known diaries from 1307-1391. I hope to present an analysis of that dataset in the coming days.

Most recent mystery month: 476-1296
Most recent mystery year: 766 BCE
Most recent mystery decade: ???
Most recent mystery century: ???

And the Chinese version.

Kudos to Berkeley Breathed (his pen name, I dunno if it’s his real name), creator of Bloom County; I can’t find the strip & ain’t got the book, but the hook was there was a day in the 80s nothing happened.
Milo is sitting in front of a TV & a local ABC reporter says something like ‘Good evening. Today, nothing happened. Over to Max Robinson in Chicago. Max, anything over there?’
Max Robinson: nothing, zip. Over to Peter Jennings in London. How about it Peter? Anything there?
Peter Jennings: Nope; bloody nothing.
It ends in the last panel Milo says something like ‘it’s Reagan’s fault’ & the original local newscaster goes ‘Nothing: is it something?’.
As a kid, it was just funny. Looking at it now, it was 1 of his best individual strips.

On average there are eclipses of the moon once or twice a year, though only about half of them would be seen in any location.