Where did you get that from? You are talking about millions of people scattered over hundreds of political entities over hundreds of years.
There might have been some commonalities, but certainly not anything like this rule.
The feudal laws of mostly Western Europe. Eastern serfdom has been much worse and much closer to slavery, however the serfs still had their house and share from the crops. The eastern European feudal lords, dukes, kings or emperors never had access to this much share of the wealth like ordinary billionaires today do.
