Enclosure, a process known in many European countries, by which commonly held or unoccupied lands or wastelands passed into private ownership. Stimulated by improved agricultural methods, the rise of a landlord class that farmed for profit rather than for subsistence, and the growth of cities as large markets for agricultural products, enclosure resulted in a tremendous increase in agricultural productivity and income. The process also resulted in problems for tenant farmers, who were often displaced without reason or compensation by landlords who wanted the land to serve their own interests. However, in its broadest aspect, enclosure was a key element in the transition from feudal, subsistence agriculture to modern, commercial agriculture.

In England, enclosure began in the 1100s. Statutes in 1235 and 1285, however, provided that enough unenclosed land must be left to fulfill the plowing and common pasturing rights of tenants. To avoid this provision, landlords frequently expelled tenants, purchased common rights, and enclosed lands after tenancies expired. The widespread enclosures—whether for farming efficiency or to convert tilled lands to sheep pasture—reduced large numbers of peasants to begging and poverty; many others joined the growing urban working class. In the 1500s the English monarchs, fearing the social unrest of a displaced peasantry, tried unsuccessfully to discourage enclosure, and in the 1600s the landlords became a dominant force in the British government. The practice gained renewed impetus in the late 1700s and was further stimulated by the General Enclosures Act of 1801. Subsequent benefits, however, were neutralized by abuses and undesirable consequences, and the Enclosure Act of 1845, which is still in effect, with amendments, subjected enclosure to close governmental supervision. By the end of the century the practice had virtually ceased. In Russia, Hungary, Germany, France, and Denmark, enclosure also was a large-scale process, mainly in the 19th century.