Subinfeudation
A knight's-fee was not only originally created by the process of subinfeudation, but could itself be split into smaller units by the same process, otherwise than through inheritance. By this means, until the practice was outlawed, a knight could create his own feudal retainer who would pledge fealty to him rather than to the overlord. Such a holding was termed a sub-fee.
It can thus be seen that the knight's fee was the base unit of land valuation for use in the feudal system.
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