Originally in Anglo-Saxon England the reeve was a senior official with local responsibilities under the Crown, e.g., as the chief magistrate of a town or district. Subsequently, after the Norman conquest, it was an office held by a man of lower rank, appointed as manager of a manor and overseer of the peasants. In this later role, historian H. R. Loyn observes, "he is the earliest English specialist in estate management".
Before the Conquest, a (Old English ; similar to the titles /gräfe in the Low Saxon languages of Northern Germany) was an administrative officer who generally ranked lower than the ealdorman or earl. The Old English word ġerēfa was originally a general term, but soon acquired a more technical meaning.
Land was divided into a large number of hides—an area containing enough farmable land to support one household. Ten hides constituted a tithings, and the families living upon it (in theory, 10 families) were obliged to undertake an early form of neighbourhood watch, by a collective responsibility system called frankpledge.
Tithings were organised into groups of 10, called hundreds due to containing 100 hides; in modern times, these ancient hundreds still mostly retain their historic boundaries, despite each generally now containing vastly more than a mere 100 families. Each hundred was supervised by a constable, and groups of hundreds were combined to form shires, with each shire being under the control of an earl. Each unit had a court, and an officer to implement decisions of that court: the reeve. Thus different types of reeves were attested, including high-reeve, town-reeve, port-reeve, shire-reeve (predecessor to the sheriff), reeve of the hundred, and the reeve of a manor.