Lisburn was enfranchised in 1661 as a potwalloping borough, but in 1795, 35 Geo. III, c. 29, restricted the franchise to the £5 householder and this reduced the number of voters to 81: before that it was much larger, and by 1818 it had declined still further, being put at 75. Its patron was the Earl of Hertford, whose estate surrounded the borough. Normally he was able to make the return with little difficulty, but he lived mainly in England and in 1783 he underestimated the strength of Volunteer feeling in the borough, which, at this time, was thought to have about 350-400 electors.39 Lt-Col. Sharman (1904) of the Union Regiment of Volunteers and Captain William Todd Jones (1123) of the Lisburn Fusiliers announced their intention of standing as Volunteer candidates for the borough. In opposition to Sharman and Jones, Lord Hertford nominated Mr Richards (1779) and Mr Moore (1446). Since 1743, when a local merchant and attorney, Edward Smyth (1946), was returned, the Conway interest had been unchallenged: this contest therefore aroused widespread excitement, increased by the neighbouring corporation borough of Belfast, where the candidates recently nominated and returned by Lord Donegall had been so completely independent of the citizens that 'they positively declined' to subscribe to 'a similar declaration to that adopted for the County of Antrim regarding their compliance with the instructions of the inhabitants of the town; attendance in Parliament; and a more equal representation of the people'.
In July 1783 delegates from the Ulster Volunteers met in Lisburn, and this assembly proposed a meeting of Volunteers from all provinces to be held at Dungannon in September 'on the subject of a more equal representation of the people in Parliament'.40 A committee was formed with Lt-Col. Sharman in the chair, to prepare for the Dungannon convention in September. It was against this background that the general election took place in August 1783. The disappointed citizens of Belfast decided to give moral support to the potwallopers of Lisburn, and 'Nearly a hundred of its respectable inhabitants attended the poll, in order to give their countenance to the free electors of Lisburn.'41 The actual election was brief. On the first day only ten electors polled for each side, and at its close the two Conway candidates withdrew; in consequence the Volunteer candidates were quickly victorious, amid general rejoicing: 'There was a bonfire in the market place, and the town was illuminated. No drink was distributed; no disturbance, riot or ill humour stained the business of the day all ending in peace and quiet.'42 Thus this most interesting election ended on a note of austerity and unexpected sobriety.
The Lisburn election of 1783 was the only one in the county where the established patron was successfully challenged, but even here, although the Hertford interest was shaken, it was a temporary setback rather than a permanent defeat. In 1790 George Hatton (0988) and John Moore (1464) were returned on the Hertford interest for Lisburn, defeating Edward Jones-Agnew (1124), a popular candidate, who along with William Todd Jones (1123) had unsuccessfully petitioned against the return of Hatton and Moore. Subsequently Jones-Agnew was returned at the by-election for Co. Antrim following John O'Neill's (1592) elevation to the peerage. Lisburn retained one seat at the Union and George Hatton won the ballot, but in the 1802 election Francis Seymour-Conway, Earl of Yarmouth, the heir to the Marquess of Hertford, was returned.