Boroughbridge was a parliamentary borough in Yorkshire from 1553 until 1832, when it was abolished under the Great Reform Act.
The constituency consisted of the market town of Boroughbridge in the parish of Aldborough (which was also a borough with two MPs of its own).
Since these properties could be freely bought and sold, the effective power of election rested with whoever owned the majority of the burgages (who, if necessary, could simply assign the tenancies to reliable placemen shortly before an election).
For more than a century before the Reform Act, Boroughbridge was owned by the Dukes of Newcastle, who controlled around fifteen seats across the country; however, in the 1790s, they sold one of the seats for £4,000 to the banker Thomas Coutts, who used it to put his son-in-law, Francis Burdett, into Parliament.
Craig (Political Reference Publications 1973) In the Boroughbridge by-election, 1819, Marmaduke Lawson was elected unopposed.