I thought it was part of China, but that is just the south/eastern part, "Inner Mongolia."
I did not know much about it. Mostly grass lands with brutal temperatures.
When things went bad in terms of climate they invaded in all directions.
Mongolia has been independent since the USSR fell. They import energy from Russia and export things to China. They used to be part of China long ago.
I linked to the modern history part at 23 min.
The Han Chinese had lived in cities and developed some immunities to diseases common in cities. They migrated into Mongolia and brought diseases that wiped out lots of the Mongols. Similar to what westerners did to native Americans.
Modern history we are taught often features the bad commies being mean to the religious institutions. That is true but .... Sometimes they were rather greedy and autocratic and the commies took their loot and freed the serfs.
https://youtu.be/NtTvgG-bKOo?t=1296
