Pocket Borough

A rotten or pocket borough, more formally known as a nomination borough or proprietarial borough, was a parliamentary borough or constituency in England, Great Britain, and the United Kingdom in existence prior to the Reform Act 1832 which had a very small electorate and could be used by a patron to gain unrepresentative influence within the Unreformed House of Commons. The same terms were used for similar boroughs represented in the 18th-century Parliament of Ireland.

A parliamentary borough was a town which possessed a royal charter granting it incorporation and giving it the right to send two of its elected burgesses as members of Parliament to the House of Commons. It was not unusual for such a borough to change its boundaries as the town developed or contracted over time, in accordance for example with the state of its trade and industry, so that eventually the boundaries of the parliamentary borough and the physical settlement were no longer the same.

For centuries, constituencies electing members to the House of Commons did not change to reflect population shifts, and in some places the number of electors became so few that they could be bribed by a single wealthy patron. These were given by 19th-century proponents of reform the derogatory appellation "Rotten Boroughs" or "Pocket Boroughs", more formally "Nomination Boroughs", because their democratic processes were rotten and their parliamentary member was effectively nominated by the whim of the patron, thus "in his pocket"; the actual votes of the electors were a mere formality, all or a majority being willing to vote as the patron instructed them. As voting was by show of hands in a single polling station at a single time, none dared to vote contrary to the instructions of their patron or contrary to what had been contracted by way of bribes received. Frequently such a borough might only put forward one candidate in an uncontested election, being nominated by the mayor and corporation at the behest of the patron.

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