How did they form? What are their specific traits? Stereotypes (even untrue, if marked as such)?
If cultural differences coincide with geography, please mention in, too.
In the questions about weird things people from different continents do somebody pointed out, that Europeans have little knowledge of this, so please fix my ignorance.
Some other publications have commented on the original more recently. For example: https://www.businessinsider.com/the-11-nations-of-the-united-states-2015-7
I thought I had seen one with some more in depth historical analysis from The Atlantic or Bloomberg or something but I can’t seem to find it again.
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