The Boundary Between Flanders And Wallonia

Belgium split in two (or three, depending on who and where you are)

Who's heard of Belgium is also aware of the the sometimes, and unfortunately, great differences between its two main regions (Brussels notwithstanding): Flanders (the Flemish-speaking, Northern side) and Wallonia (the French-speaking, Southern portion).

What is really interesting, however, is that though this separation hasn't always existed (indeed, Belgium used to be a Celtic country before the "Germans" and Romans invaded them), this boundary between the two regions is perhaps much older than one might think, and takes us all the way back to...

358 C.E.