Some are easy. Wisconsin is seperated from Iowa by the Mississippi River. But how did they decide It would end where Illinois begins? Why aren’t any states shaped like a circle or a triangle? Who, how, and why did the decide where New Mexico ends and Arizona begins? Why is Idaho shaped like that?
Wow. This thread will need at least fifty replies. Every state has it’s own involved birthing story.
Like Vermont, which Ethan Allen championed into existance from land disputed by NY and NH. (He hated us “Yorkers.”) Vermont borders remain messy to this day: usually a river that divides two states is split down the middle; not so with the Connecticut River between VT and NH. NH, I believe, owns the whole thing, shoreline to shoreline – and therefore gets stuck with all the bridge maintenance bills.
And there’s West Virginny, born of the Civil War anti-slavery sentiment in the western end of a once-larger Virginia.
Regarding geometric shapes, the northern border of Delaware is drawn as a perfect circle with, IIRC, a courthouse as it’s exact center. Why? Dunno.
And there’s the whole issue of the “Western Land Claims” that the eastern states “reserved” for themselves before the Articles of Confederation.
Yeesh, this is going to be a long (but fun) thread…
I believe Delaware was originally the southernmost four counties of Pennsylvania. Someone probably plunked down a courthouse and declared it’s jurisdiction as everything within a given radius.
Hawaii’s border was pretty easily decided.
Pennsylvania’s border with Maryland is a line of latitude surveyed by Mason and Dixon.
Many of the Colonies’ shapes were dictated by the land grants from the King. From the looks of Massachusetts’ southern border, they were pretty badly surveyed and just stuck.
another SDMB member posted this recently…(I forget who at the moment… sorry!)
Yup, I agree that there are many interesting reasons for borders. This will be an interesting thread I imagine.
Just to throw my two cents in, I watched with interest one of the most recent border disputes in the USA - New Jersey v. New York over Ellis island. The result is a strange border indeed. I believe that the Supreme Court ruled that all of the original island belongs to New York. Everything that is “fill,” belongs to New Jersey. As I recall, the island is now sort of a rectangular dumbell shape. Most of it is New Jersey, except for an oval shaped section in one part. Looking at a map, it’s truly odd.
Here’s a good thread:
http://boards.straightdope.com/sdmb/showthread.php?threadid=15215
There are many more than fifty stories here, because ach boundary is its own story, and they can change with time (look at the complicated Missouri-Kentucky-Indiana border). Why is the New York/Massachusetts-Connecticut-Vermont border EAST f the Hudson River instead of on the river? Howcum the “sides” of Colorado and Wyoming aren’t straight? Why does a little bit of Massacusetts “blip” down into Connecticut and a little bit of Minnesota “blip” up into Canada?
I personally think the border dispute between Ohio and Michigan is more interesting (hey, call me biased, but I grew up in the disputed area).
It was called the Toledo war. At the time, one would have predicted that Toledo would become a major transportation hub (one would still predict it, but it ain’t happening). Nonetheless, Michigan and Ohio fought over who had the rights to Toledo–and when I say fought, I’m not talking about suits arguing in a courthouse. They came out with guns a-blazin’ at first. Eventually Congress settled the dispute with a compromise: Ohio would get to keep Toledo as well as a small sliver of Southern Michigan. In return, Michigan got the entirety of the Upper Peninsula.
In Toledo, we joke that Ohio lost, big time. 
(I bet you always wondered why Michigan had the U.P. Though what I wonder is why Virginia owns that tiny sliver of the Delmarva peninsula.)
LL
I was just about to post on the Toledo war, and ya beat me to it. The borders for Michigan, Ohio, Indiana, Wisconsin and Illinois were originally determined by the Northwest Ordinance, IIRC. Ohio got bossy and stole Toledo, so we got the western part of the UP in compromise (the eastern part was already ours).
That Ohio State/Michigan rivalry goes back aways 
Actually, that goes for the MD/DE border as well. The AAA atlas I was using the other day clearly indicated that the Mason-Dixon line took a right at DE and trucked down the Delmarva Peninsula before taking a left and heading out to sea.
Same thing for MD and VA. MD owns the whole of the Potomac tidal basin; the VA border runs along the shore.
I have a feeling the straightedge borders more commonly found towards the Mississippi have to do with the way land was divided up for settlers; the lots were perfectly square (40 acres?) and so it was pretty easy to set up a state line once the settlers decided to join the Union.
One thing about the Toledo War puzzles me. Did Ohio have the UP originally? That seems really wierd. And if it didn’t, why would a compromise between Ohio and Michigan involve Minnesota?
Actually, it involved Wisconsin, for which the UP was originally destined. But at the time, the UP wasn’t part of any state, just territories, and the Congress basically had the ability to divy up territories that weren’t owned by states any way it wanted to. So they gave MI the UP, and Wisconsin could like it or lump it, as it were.
LL
There were only a few thousand people in Michigan at the time, and Wisconsin was probably even more sparsely populated. Well, not counting Native Americans, anyway, which of course were probably not counted as citizens for representation. That’s another discussion altogether.
I’ve heard a legend that says that the western border of Montana was originally supposed to be the Continental Divide. Well, the southern part of the border starts out that way, but then it follows the Bitterroot Mountains, veering hundreds of miles away from the Divide. Ooops. (I think the “mistake” was supposedly deliberate, though.) It gave Montana much of the mineral wealth that gave it its old nickname, the Treasure State. Sorry, Idaho.
If you look at Idaho, though, doesn’t it look like “the state of what was left over.” Oklahoma looks that way, too, with that “panhandle”. Of course, Oklahoma was “left over”…it was the land that wasn’t part of any state that they dubbed “Indian Territory.”
I don’t know if this story is true or just a legend, but here goes…
If you look at a map, you will note that Staten Island is a lot closer to New Jersey than to any part of New York. So how did SI end up in the Empire State?
Legend has it that in colonial days, New York and New Jersey argued over this island. Eventually, the matter was settled by a boat race around the island by the governors, which New York won.
If anyone has any info on whether this is true or not, I’d appreciate it.
Zev Steinhardt
My favourite border anomaly is one that seems pretty obscure: A small section of Delaware East of the Delaware River (almost Delaware Bay at that point), firmly attached to New Jersey - the Supawna Meadows NWR (or something like that) according to Rand McNalley. Even better, a few miles south of that, there’s a micro-chunk of Delaware on New Jersey’s Stoney Point Pennisular (the Atlas is a little vague on names in this location).
There’s gotta be a bar-bet in there somewhere.
Almost, I thought this way until a few months ago, the MD/VA border is a mess, MD owns a lot of the river but in some spots it gets split down the middle and at other times VA gets the river. you really need to look at a large scale map.
Most of the Mid-Western States, NE,KS, MO, OK, NM, AZ etc. are split along lines of longitude, how they chose those lines I don’t know but that’s why they are straight. Most of the counties in those states look that way too. it does have to do with the way that they split up the land when the Gov was selling it.
Minnesota blips up into Canada because of a cartographical error.
Oklahoma and Texas are divided by the Red River. They still don’t completely agree on the whole thing. Here is an article about it.
Well, ya’ll ‘member the story of the Mason-Dixon Line from studying the War Between the States, right? That there is why Missouri’s southern border has it’s bootheel (pronounced boot-hil). In order for Missouri to be a Southern state and allow slavery to be legal it had to steal some of Arkansas’ territory. (I remember cracking my teacher up while studying this. I said something to the effect of, “Since slavery is illegal now, shouldn’t we give it back?”) Why did they choose that particular part of Arkansas to put with Missouri? Well, you see, that’s all swamp land there. Arkansas didn’t really care if they had it or not. They weren’t always the “Natural State”.
The rivers are obvious borders. I have no idea how they decided the borders between Iowa and Kansas/Oklahoma. Anybody?