I presume he's referring to when diets are held which are organized according to the medieval European concept of the Three Estates.
en.wikipedia.org
Of course as you say nearly all the world has aristocrats, merchants, and priests. But their specific organization in this way with pre determined allotments at diets is as far as I know a European thing. I'm not saying 'interest groups on other continents had no official say in their realms, and were not present at meetings' but rather 'the specific setup of the 3 estates meeting in this general way is European in origin'.
I believe (almost) all larger societies had groups / classes, which shared sbd/or competed for power in their standard way of councel.
--> that is a parliament gameplay-wise.
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I know, I know there are tendencies
- to see the same pattern everywhere
- to say my or the dominsnt way is special and never reached.
But sometimes generalisations, which might be slightly off, are ok.
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Finally, your wiki-article to me basically shows that its topic does not exist, because of all examples given only the first one had 3 estates and everyone else had 2, 4, other other. Also the description is vague to the extreme.
Of course this is not meant totally honest. Calling (parts of) societies "estates" is helpful.
But just as the Holy Roman Empire was neither of it, the 3 estates of Europe, were not 3, ill defined and not exclusive to Europe.
