From the cited source:
Stalin is an uncommon figure in modern economic history: a dictator with absolute power who also controlled one of the largest economies in the world. Since it is virtually impossible to separate Stalin's wealth from the wealth of the Soviet Union, this combination has led multiple economists to nominate him as one of the richest people of all time.
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While that money didn't belong directly to Stalin, he had the ability to leverage blah blah blah peepee poopoo
Neolib ghouls are absolutely wild.
Uhh.
I mean I'm not much of a historian but Mansa Musa crashed the world's gold economy from giving away too much gold when he went on Hajj and Ghengis Khan ruled over everything between the Chinese coast, Poland, and the Sahara. I think it's going to be hard to beat either of them.
Spain pulled the same trick in the 1500s, after looting the combined wealth of Inca and Aztec empires. Then their navy promptly sank into the ocean when they picked a fight against the UK during hurricane season.
Like Macedonia's Alexander the Great, Ghengis Khan didn't so much rule these regions as do a Hell's Angel's style joy ride through their center and kill anyone who looked at his army crosswise. The "empire", such that it was, never established a formal bureaucracy outside of the far eastern provinces and immediately collapsed into infighting on his death.
I'd call them some of history's biggest moochers and looters. But I think you need to look more towards Augustus Caeser, the Eisenhower Administration, or the Tang Dynasty if you want to talk about a handful of individuals dictating the management of a plurality of global productive capital.