Monopoly is the power to control economic activity in some field or situation. Monopolies may exist naturally, be established by law, or arise in the course of competition.
Concentration of capital
In late feudal and early modern European cities guilds, associations of craftsmen, customarily controlled skilled trades. Guilds had an apprenticeship system which trained youths to become journeymen skilled in a craft, then masters who operated workshops employing journeymen and training apprentices.
In early modern Europe the crown actively engaged in direct regulation of trade, a system of mercantilism, freely granting monopolies to favored persons and associations. A modern form of mercantilism was used in Japan to promote industrial development in the late 19th and 20th centuries.
Natural rustic monopolies
In rural and village settings natural monopolies in trade are typical due to lack of trade sufficient to support competition. Custom and ownership patterns also play a role.