Here be swamp rabbits.

June 1, 2016 2:05 PM

How old is your map? A handy guide from xkcd.
posted by phunniemee (39 comments total)

"One, but it's huge" 41-45.
posted by Mitheral at 2:09 PM on June 1, 2016 [8 favorites]

This is neat, thank you! I've thought about posting an Ask about how I can tell how old a map/globe is so I'll seem smarter and this is excellent. I also like the bit in the middle with Mordor and Narnia and so on.
posted by Mrs. Pterodactyl at 2:14 PM on June 1, 2016

Hmm. A less lazy person than I could take Wikipedia's List of world map changes, code it by country and year, and produce an optimal decision tree for this kind of thing.
posted by jedicus at 2:19 PM on June 1, 2016

This flow chart posits a world of maps, tubas, staplers, breadboxes, cats, seagulls, and you.
posted by Going To Maine at 2:21 PM on June 1, 2016 [3 favorites]

See also Replogle's "How Old is Your Globe?" and this article which goes back to 1817.
posted by jedicus at 2:23 PM on June 1, 2016

Now I want to find old maps to test this with.
posted by figurant at 2:23 PM on June 1, 2016 [1 favorite]

This was a very useful flowchart for me. I can now stop trying to refold this damn seagull.
posted by bologna on wry at 2:26 PM on June 1, 2016 [33 favorites]

Already asked. I wonder how much Randall reads Metafilter.
posted by Melismata at 2:28 PM on June 1, 2016 [9 favorites]

Big lake in southern California?
posted by Stonestock Relentless at 2:28 PM on June 1, 2016

I like the line to "did you make this yourself?" "Yes" "it's very nice"
posted by The Whelk at 2:29 PM on June 1, 2016 [11 favorites]

Big lake in southern California?

The Salton Sea.
posted by JiBB at 2:36 PM on June 1, 2016 [6 favorites]

Look out, Coloradans
posted by Monochrome at 2:36 PM on June 1, 2016 [4 favorites]

I also appreciate that it includes a guide to the age of your Middle Earth map.
posted by sleeping bear at 2:37 PM on June 1, 2016 [6 favorites]

"Weird recursive heaven"
posted by schmod at 2:39 PM on June 1, 2016 [4 favorites]

Wait, so, if I can't see Istanbul or Constatinople and the Ottoman Empire doesn't exist, but North Korea does and so does Zaire, then it must be 1992-96? That's like...maybe not false, in the strictest sense, but also not exactly how flow charts are supposed to work.
posted by The Tensor at 2:44 PM on June 1, 2016

I wonder how much time it took to figure this out....
posted by miyabo at 3:49 PM on June 1, 2016

the Ottoman Empire doesn't exist, but North Korea does and so does Zaire, then it must be 1992-96?

You can only get to that part by also saying that the USSR doesn't exist.
posted by Hatashran at 3:53 PM on June 1, 2016 [1 favorite]

Even by xkcd's normal high standards, this one is pretty delightful.

One of my all time favorites is also map-related: What your favorite map projection says about you.
posted by simonw at 3:56 PM on June 1, 2016 [5 favorites]

He didn't have to say that about Saint Trimble's Island. It's very nice, although you should bring a warm coat when you visit. Even in summer, yes.
posted by ardgedee at 4:39 PM on June 1, 2016 [3 favorites]

This goes well with the video of an animated map of all empires over the last 5,000 years, which I just watched, fascinated.
posted by Mapes at 4:56 PM on June 1, 2016 [5 favorites]

Thanks! I'm turning this into a poster for my classroom.
posted by wester at 5:28 PM on June 1, 2016

I'm watching that video and the spread of the Mongol Empire in the 1230s is insane!
posted by andrewesque at 5:30 PM on June 1, 2016

Now it's Istanbul not Constantinople? Why did Constantinople get the works?
posted by TedW at 6:19 PM on June 1, 2016 [5 favorites]

That's nobody's business but the Turks'.
posted by asperity at 6:41 PM on June 1, 2016 [8 favorites]

What if my map lists Old New York as New Amsterdam?
posted by schmod at 8:13 PM on June 1, 2016

Great song to launch into when you're with ur Greek Cypriot gf.
posted by nom de poop at 8:16 PM on June 1, 2016

Fantastic overall, but a tad disappointed by the Jimmy Carter branch, which seems like a cop-out. That really doesn't make any sense to anyone other than Presidential politics enthusiasts. You'd want a flow that's purely based on what you see on a map.

Here's how I'd enhance it, with some South/ South East Asian signs: Observe the Pakistan - India - China border (which also will tell you where the map was published) and the various contemporary countries in South East Asia: Ceylon or Sri Lanka? FMS or Malayan Federation or Malaysia? East Timor or Timor Leste, and is it shown as belong to Indonesia, Portugal or being independent?

Also, depending on the vintage (and mostly true for atlases), it's useful to see what area is marked as "Middle East", is it the countries around the Arabian peninsula or the region between the Persian Gulf and India?

Loved the Africa portions quite a bit, especially Upper Volta versus Burkina Faso. Would have been even better to somehow include South Sudan, which really is the main factor to see for maps that you may actually buy in a bookshop.
posted by the cydonian at 8:59 PM on June 1, 2016 [2 favorites]

Welp. Looks like I'll be leaving Colorado in a few years...
posted by asperity at 9:04 PM on June 1, 2016 [1 favorite]

Disappointed it covers those Colorado arachnids but misses the Kanga Rat Murder Society.
posted by N-stoff at 9:05 PM on June 1, 2016 [6 favorites]

Okay, weird maths + cartography question here: would it be possible to use the four colour theorem to date a map?

Because the shifting borders of states coming into or going out of existence change the dynamics of colouring, there must be a finite number of ways of colouring a map in any given year. So, for example, you could say, "if France and China are the same colour, the map can't date from 1954". I suppose there are a lot of variables here (especially as diagnostic states might not exist) but what is the possibility?
posted by Emma May Smith at 9:17 PM on June 1, 2016 [6 favorites]

I don't know either but that's a fantastic question
posted by vibratory manner of working at 1:09 AM on June 2, 2016 [1 favorite]

In the UK there are map colouring traditions also which might help.
For example the empire was coloured in pink.
This is a tradition which sort of lives on, so you'll often see ex-empire (or more often just commonwealth) countries done in pink.
I believe that Dutch owned territories were often done in Orange and French in Blue?
posted by Just this guy, y'know at 2:30 AM on June 2, 2016

There would seem to be too many choices to identify just on colours; every single border is a recombine branch and every map maker is going to make different choices at each of those branches. And there isn't even an agreed upon number of colours to limit a map to. The previously linked empire status video is a good example of the worst case; each empire is assigned a unique colour.

If I understand the math right with our current 195 countries and allowing a unique colour each you have 195! possible combinations of colours or 2xa10³²⁹. And that ignores all the repeat cases with fewer colours. Perspective check: there are upwards of 10⁸⁰ atoms in the universe.

In addition the four colour map theorem can't actually be used to colour a world map because it breaks when you have non-contiguous and enclave areas.
posted by Mitheral at 2:54 AM on June 2, 2016 [5 favorites]

Mitheral, you win the daily excellent answer that is simultaneously a huge let down award. Feel free to swing by and collect your tear-filled chalice at any time.
posted by Literaryhero at 4:09 AM on June 2, 2016 [1 favorite]

As Mitheral says, graphs don't model cartographic maps accurately enough for the 4 Color Theorem to apply in general. Ignoring that, I think the way it could possibly apply is if the test was more like "In all possible 4-colorings, do France and China have the same color". That really gets at the structure of the map, but is too hard a question to be of practical use.
posted by Horselover Fat at 5:07 AM on June 2, 2016 [1 favorite]

So here's a list of English language world maps currently online at the Library of Congress. I had a blast checking a bunch of them against the flowchart. Of course the less detailed ones make it difficult.
posted by numaner at 8:36 AM on June 2, 2016

You could also check against the maps in Stanford’s David Rumsey Map Collection Database.
posted by Going To Maine at 8:42 AM on June 2, 2016

This is fantastic.

My nitpicky self wonders about finding a map from 1948-1952 with I-25 on it.
(for the Hot Springs/Truth or Consequences question)
posted by MtDewd at 9:44 AM on June 2, 2016

HEART EYES EMOJI
posted by dry white toast at 4:58 AM on June 3, 2016