Brit here, I only realised a couple of years ago that the Arkansaw I heard mentioned in American TV and movies was actually the Arkansas I could see on maps. I think it was something said on Reddit, probably a thread similar to this, that was the revelation. And when I tell other Brits they're invariably similarly clueless, and quite gobsmacked. I'm not sure if anyone I've mentioned it too has said "oh yeah I knew that".