Japanese probably did control a tiny bit of Mongolia e.g in the Tauran Incident, the Japanese won and occupied village of Tauran and surrounding areas which is now part of modern day Mongolia.
Would Russia make the cut in that case? And I agree with others, parts of modern-day Mongolia were controlled by Japan thanks to invasion attempts and the borders of the country not entirely corresponding to its modern-day ones. Might be reasonable to change the country to something else.
I can’t find any evidence whatsoever that Japan actually occupied any amount of present-day Mongolia. Japan took Inner Mongolia, but of course that’s part of China today. At most, there were clashes in Mongolian territory that were driven out by the Russians. Japan simply didn’t EVER annex any part of modern Mongolia. Unless someone can provide actual evidence from an academic source, Mongolia stays a viable answer.
Alright, apologies for not providing any sources on my initial comment. Now I've researched the topic more and I'll attempt to explain myself a bit better.
First, my claim that the Mongolian borders were a bit different was something I learned from Dekkie a while back; that was due to the ongoing Chinese Civil War and the borders not being properly defined for a good while after independence. Case in point: they included slivers of present-day Mongolia being occupied by Japan in this quiz: [1]
This "changing border" claim is evidently not something that is discussed outside of maps. Nevertheless, academic sources do prove that the border was not defined and the modern one was only adopted after WWII ([2], Bataarkhuu, Ph. D., 2023, p. 2-3)
This claim is also supported in this work: [3] (Bellamy; Lahnstein, 1990). It also highlights my other claim about Japan's "invasion attempts". Khalkhin Gol is a river along the Mongolia-China border that at one point, defined their border and left an area between Nomonhan and the river as disputed territory ([3], p. 20). This area is part of Modern-day Mongolia. Japanese army did engage militarily there and invaded some of it, but were pushed back to Manchuria by Soviet forces ([3], p. 30; [4] (good old Wikipedia for good measure)).
I hope I managed to explain the situation a bit clearer now, providing academic sources to back up my rambling and everything. The borders were messy in Mongolia's first years of independence, Tauran was not the only conflict related to modern-day Mongolia the Japanese engaged in, being pedantic is fun.
So, the question becomes... do the border clashes amount to Japan actually taking land? I mean, I can't really argue with dekkie though. No one is going to do more research than dekkie. I think I'll just use that as a guide to my answer key, especially since it's a featured quiz.
Thank you for listening to feedback! Changing the answer altogether, as I previously said, is also a better decision imo, as it clearly is very debatable. It's a whole can of worms.
Ok, after researching Tauran a LOT more than I wanted to, I’m not counting it. Mongolia went and planted their flag there, since it was a disputed border village that Japan claimed to own but had never even been to. This made Japan angry and they sent a small force to remove the flag. After a clash, they took down the flag. Russia told Japan to get out and the town would be considered neutral, and Japan withdrew pretty much immediately. I don’t think there’s any reason to think Japan actually “owned” Tauran. All they did was take down a Mongolian flag, fought for a day, and left.
They weren't affected, but it's a plausible guess.
First, my claim that the Mongolian borders were a bit different was something I learned from Dekkie a while back; that was due to the ongoing Chinese Civil War and the borders not being properly defined for a good while after independence. Case in point: they included slivers of present-day Mongolia being occupied by Japan in this quiz: [1]
This "changing border" claim is evidently not something that is discussed outside of maps. Nevertheless, academic sources do prove that the border was not defined and the modern one was only adopted after WWII ([2], Bataarkhuu, Ph. D., 2023, p. 2-3)
I hope I managed to explain the situation a bit clearer now, providing academic sources to back up my rambling and everything. The borders were messy in Mongolia's first years of independence, Tauran was not the only conflict related to modern-day Mongolia the Japanese engaged in, being pedantic is fun.
Ok i read the caveat.