This @AmericanGeo piece explains quite succinctly the modernity of national borders (and the nation state). It's also where the "less than 1% of current borders were created before the year 1500" fact comes from. By Abigail Vandenberg.

@edanderson101 I showed a map of the Holy Roman Empire in the 15th century with its hundreds of dukes, princes, bishopries and we electors to students of European state formation to show how recent many of our national borders are

@SteaknGidney That's a good one. I've also showed 18th/19th century maps of 'Germany' & 'Italy' for the same reason (after asking them to says things about German/Italian national culture). But there's something particularly powerful about the video, watching borders physically move over time.

@edanderson101 I quite often show this kind of thing to students (there are a few on youtube). But I always add that each lightning fast shift is years, decades or a lifetime of political turmoil, strife, war or (if lucky) hard fought negotiation. So they don't think borders move by themselves.

@kilderbenhauser This is a very good point. Any 2-3 seconds of this video is a whole field of study in history, and could take an entire module to cover!

@edanderson101 Do you know where the video comes from - from the point of view of attributing its creator if using in a lecture? Thanks for sharing!

@Michaelacbenson Not entirely sure, unfortunately. It's been shared numerous times, on multiple platforms, across many years. But I have seen some versions with a watermark of Historical Atlas, which seems like the most likely source:

@SushmaJansari Yes! They tend to be borders that are defined by geographical features rather than more 'arbitrary' lines.

@edanderson101 WOW!!