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That should be the United States of America

you can see the tags, i think Asia (China, Indonesia, Thailand) is strong, but also USA, Latin America and Europe

An interesting method in trying to figure it out, I saw this question and wondered if anyone would be able to give a more informed answer so think this is a step in the right direction. Maybe the best we have at the moment is communities as you say.

I don't think anyone will be able to answer this truly though as there it's not logged anywhere I believe, maybe by the Dapps, but not in the blockchain itself.

You just can see the volume of posts. Currently Korea, Latin America and Indonesia are strong
Screenshot from 2018-09-01 00-52-32.png

But you can't know exactly.. maybe you can compare the "steemit" popularity on Google trends

Whenever i look at the “kr” tags and the number of users on that platform one could easily tell that we have alot

of koreans on the steemit platform,,i think the country with the highest number of users on steemit is south

korea then followed by united state of america then followed by nigeria....

The US has the most users by a fair margin...but I think that you may be onto something, that it may indicative of who has the most "users" actively posting. I've been gong through my followers list and clicking one at a time. Many have not done any posting in a long time. I've done this before myself but I wonder how many post and do activity when the Steem is up and vs when it's down?