In feudal Anglo-Norman England and Ireland, a knight's fee was a measure of a unit of land deemed sufficient from which a knight could derive not only sustenance for himself and his esquires, but also the means to furnish himself and his equipage with horses and armour to fight for his overlord in battle. It was effectively the size of a fee (or "fief" which word is synonymous with "fee") sufficient to support one knight for one year in the performance of his feudal duties of knight-service.