The slime!

It's where the Mississippi River was at the time (and still largely is). It's not like someone just drew it that way.

I believe it's actually because Tennessee became a state in 1796, but rulers weren't invented until 1797.
- Rulers were invented like 3,000 years before that.
  It is a funny picture to think of some Tennessee hillbilly surveyor with a 1ft ruler trying to count out the border though.

Does a river run along that goofy looking border?

Yes. But the border is drawn where the river used to be.
Yup, the Mississippi
- Rivers are almost always the culprit of goofy looking boarders
I think most rivers look like that given enough time and erosion. I don't remember the explanation but I half remember reading that just about any curvy river has carved its riverbed into that shape over very long periods.
- water moves faster along the outer bends, giving it an increased capacity for carrying sediments. this results in erosion happening faster near the outer curves. on the other hand, water is slower near the inner bends, forcing the sediments carried by the river to deposit there. this interaction makes the rivers more bendy. an interesting result of this phenomenon is the formation of oxbow lakes (those c-shaped bodies of water separated from the main river)
  Yamal Peninsula, Russia
Indeed. Also the little balloon shaped thing in the north west is actually part of Kentucky, but separated from the rest of the state by the river.

Americans seeing borders based on natural features instead of straight lines for the first time:

That’s on western Americans. Over on the East my state’s north and south borders are defined by water features
- In Oregon, our northern and eastern borders are mostly defined by rivers. From my perspective, it'd be eastern Americans that don't get it...

People saying "ya it's called natural borders yank" as if they don't come from countries where borders are decided instead by whoever was fucking over whichever disenfranchised minority group at any given time.

Also I actually think borders should be set at watershed boundaries instead of rivers since a lot of cities end up sprawling onto both sides of a river divide. The continental US should have 8 states,

Longhouse at the North Eastern watersheds,
Sherman along the southeastern, Tennessee Valley, and lower Mississippi watersheds
Ohiagan along the Ohio, Great Lakes, Upper Mississippi, and Sourris Red watersheds
Texas along the Rio-Grande and Texas Gulf watersheds
Buffalo along the Missouri and Arkansas watersheds
Sierra along the Colorado and Great Basin watersheds
California at the California Watershed
Cascadia at the PNW Watershed

Counterpoint: I ain't sharing a state with missouri
- silence Missouri toucher
Rename the Southeast to Sherman? I would like to subscribe to your newsletter.
Ohiagan
🤮🤮
- A chance to undo Ohio and he only made it bigger
- I mean the only other option that'd even kinda work for the whole region is Tecumseh
Fun fact: watersheds are how we define our regions in NZ.
Though a region may consist of more than one watershed, but not less than one or a partial one.
What happens when the river moves though?
- WAR!!!
- Nothing, the watershed boundaries are the points where water stops flowing towards one body of water and starts flowing towards another.
You can't make me do anything with Ohio

I invite you to look up the town of Baarle-Hertog/Baarle-Nassau and surrounding area. I would love to describe the area as "on the Dutch/Belgian border", except there isn't really much "on" going on there. Seriously, have a look and tell me I'm wrong.

Linked because I haven't yet learnt to put screen shots in comments.

They place looks like it got bombed in WW1 and the bombing literally broke the borders
Linked because I haven't yet learnt to put screen shots in comments.
You've gotta upload the screenshot to some third-party service. There's no built-in way to do it.
Then you insert it with ![](Url)

The northern border is only so janky because it follows the Mason-Dickhead line.

How dare you. Jeremiah Dickhead was perfect, and so is his line.

is more suspicious of the "straight" lines supposedly projected into a globe

Goofy?

Angry European noises

I live in the slime zone

I live opposite to the slime. My border is nicer, but we live under constant threat of meeting people from the shitty part of Virginia, so it's not much better.

That, my friend, is the product of rampant incest.

We're talking about the BORDER, not the actual state
- Edges make cousins.