 This was a development of the feudal concept of fief (in which a lord was obliged to raise a certain quota of knights, men-at-arms and yeomanry, in return for his right to occupy land).In practice, noblemen and professional regular soldiers were commissioned by the monarch to supply troops, raising their quotas by indenture from a variety of sources.A Commission of Array would be used to raise troops for a foreign expedition, while various Militia Acts directed that (in theory) the entire male population who owned property over a certain amount in value, was required to keep arms at home and periodically train or report to musters.