Nope. Not by an "oath". By debt. Check your history books.
Nope. Not by an "oath". By debt. Check your history books.
Feudal serfs were bound to the 'land' in a sort of debtor-lendor scenario, and could be sold along with the land beneath their feet. They just couldnt' be sold as individuals.
However, knights, squires, barons, etc. were bound to serve their superiors by oath. Its the oath that kept the political and military structure together.
There still was debt to be paid even by knights. Every year the debt obligation had to be met via service or hard ca$h.
EDIT: changing "lords" by knights in the Middle Ages was common. I.e. for few years a knight served a French king just to serve German Prince for a few years after that. So, it looks like they couldn't have taken their oaths too seriously or there had to be an easy way to have the whole thing cancelled.
Don't remember the exact date or edict name, but when in the Roman Empire a law was introduced banning debtors from moving too far from their creditors - that's when according to many historians Middle Ages have started.
The usual explanation for the emergence of feudalism in Western Europe involves market forces as well. As people fled the starving cities at the collapse of the Roman Empire, they had little choice but to agree to whatever terms rural estate landowners offered, which were generally not favorable terms.
I think one reason a sort of libertarianism was popular in the early U.S. is that there was always an alternative option: go to the frontier and homestead. So people really felt that they had individual freedom, and could escape any onerous sharecropping arrangement by just heading west. But in Europe all land was already spoken for, so there was nowhere to go homestead.