Kind of like how walls were used around city states in Mesopotamia? Or how there was a wall created in China? [1] has some discussion on walls being used for de

Kind of like how walls were used around city states in Mesopotamia? Or how there was a wall created in China? [1] has some discussion on walls being used for defense in each of those areas. I'm in no way an expert on history, but it seems that walled city states developed in many areas independently. People seem to generalize or abstract ideas, so if you have a city state, why not think bigger and have a nation state? From what I understand, again no expert, modern nation state borders are something that came from Europe [2], but a Sumerian king was the first to use a wall to mark a "national (rather than private) boundary"[1]. Walling off areas is in no way a uniquely European concept. [1] https://www.worldhistory.org/wall/ https://www.worldhistory.org/wall/ [2] https://en.wikipedia.org/wiki/Westphalian_sovereignty https://en.wikipedia.org/wiki/Westphalian_sovereignty