A Map of Shadows

[Diamond]

I don't think those are meant to be hard borders, really. South of those borders is land occupied by various "desert tribes". I think when your land borders a nomadic, ill-defined, or porous peoples, then your "borders" with them are going to be nomadic and porous - basically the border is where your defensible settlements end or where the extent of your authority and influence drops below a certain threshold.

Basically, I think you're right that borders between sovereign nations with governments that can reach the entirety of their claimed lands tend to be along straight lines or follow "jagged" natural boundaries, but I don't think "desert tribes" counts as a sovereign nation in the traditional sense.

Got it in one.

Although historically the Ottoman Empire laid claim to just about all of North Africa, their influence south of the coasts was poor at best. It wasn't until the European powers really got crazy with the whole colonialism thing in the late 19th century that those places were 'claimed'.

[DungeonMasterGaz]

This is a beautifully rendered map. It reminds me of the sort of thing you might get in an alternate history, strategic-level boardgame. Perhaps like Diplomacy, or something.

I hope you get to use it in some way.

DMG

[Diamond]

Thanks! I appreciate it.