Since the Norman invasion, a chain of self-governing municipal boroughs had been established in Ireland, chiefly in the more heavily settled provinces of Munster and Leinster. A municipal borough or borough corporation was a self-governing town and the granting of this privilege was known as incorporation, which involved receiving a charter or written constitution (generally supplemented by later charters and the evolution of unwritten customs and conventions). Municipal boroughs were usually governed by a propertied minority known as the burgesses or freemen, who constituted the civic electorate and met weekly in a combined town council and law court called the ‘hundred court’ to transact legal and administrative business. At a special annual meeting they elected a chief officer, called the mayor, provost, portreeve, burgomaster or sovereign. Later, smaller and more exclusive common councils evolved, equivalent to the modern city or town council, eventually displacing the hundred courts, to become the most powerful representative bodies in the towns. Whatever the details of individual charters, in practice the mayor and council tended to be chosen from among a small clique of the wealthiest families, closely related by birth and marriage. Municipal boroughs discharged a variety of local government functions and were also parliamentary constituencies, generally returning two members each.