A rotten borough was a parliamentary constituencies that had declined
in size but still had the right to elect members of the House of Commons.
Plympton Earle had been a prosperous market town in the Middle Ages
but by the 19th century it had declined to the level of a country
village. Newtown on the Isle of Wight had been a market town but by
the time of the 1832 Reform Act it had been
reduced to a village of 14 houses.
Most of these constituencies were under the control of one man, the
patron. Rotten boroughs had very few voters. For example, Dunwich
in Suffolk, as a result of coastal erosion, had almost fallen into
the sea and by 1831 only had thirty-two people had the vote. Old Sarum,
in Wiltshire, only had three houses and a population of fifteen people.
With just a few individuals with the vote and no secret ballot, it
was easy for candidates to buy their way to victory.

W. Heath's cartoon
How to Get Made and M.P. (1830)
| Borough |
Patron |
MPs |
Houses
in Borough |
Voters
in 1831 |
| Bramber |
Duke
of Rutland |
2 |
35 |
20 |
| Callington |
Lord
Clinton |
2 |
225 |
42 |
| Dunwich |
Lord
Huntingfield |
2 |
44 |
32 |
| East
Looe |
John
Buller |
2 |
167 |
38 |
| Gatton |
Sir
Mark Wood |
2 |
23 |
7 |
| Old
Sarum |
Earl
of Caledon |
2 |
3 |
11 |
| Newtown |
Sir
Fitzwilliam Barrington |
2 |
14 |
23 |
| Plympton
Earle |
Earl
of Mount Edgcumbe |
2 |
182 |
40 |
(1)
Tom Paine, Rights of Man (1791)
The county of Yorkshire, which contains near a million souls,
sends two county members; and so does the county of Rutland which
contains not a hundredth part of that number. The town of Old Sarum,
which contains not three houses, sends two members; and the town of
Manchester, which contains upwards of sixty thousand souls, is not
admitted to send any. Is there any principle in these things?
(2)
William Wilberforce, describing his
election at Hull in 1807.
By long-established custom the single vote of a resident elector
was rewarded with a donation of two guineas and the expenses of a
freeman's journey from London averaged £10 a piece. The letter
of the law was not broken, because the money was not paid until the
last day on which election petitions could be presented.

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