Londonderry city was among the most important and the most complex of the parliamentary boroughs. It was more of a county borough than a borough. Its electors were the freemen and freeholders of the city. It had a mayor, aldermen, common council and freemen by birth and grace especial. Most of the freemen were absentees and had been made by the corporation. In 1783 there were about 750 electors; it was estimated that these had risen to 1,000 by 1812. Londonderry was the principal port of the north-west and, like Belfast, with which it had certain similarities, it was a city of merchants - 'Many of whom are truly independent, as well in mind as in fortune.' To a certain extent it has always been a city of cultural diversity. When it began to develop after the siege it had a strongly Scottish and Presbyterian flavour. This was shown by the consequences of the 1704 penal law, when 12 aldermen, six of whom had been mayors, and 14 out of 24 burgesses were removed from their municipal offices.253 Possibly there had already been a certain amount of friction in the corporation, as in 1698 some of the aldermen and burgesses signed a declaration to the effect that alderman Thomas Moncreif 'has been deliberately excluded from the mayoralty by a combination among the Dissenting aldermen and burgesses'.254
Two elections illustrate the nature of politics in the city. The 1747 by-election following the death of Frederick Cary-Hamilton (0364)255 was hard fought between Henry Hamilton (0930), agent for the Hollow Blade Company and from 1755 agent-general for the Irish Society, and George Vaughan. The result, according to Lord Abercorn's agent, John McClintock, was 334 for Vaughan and 324 for Hamilton: some of Vaughan's votes must have been discredited, as Hamilton was elected. It was rumoured that Vaughan's expenses were about £2,500 and Hamilton's about £1,300.256 Vaughan petitioned the House of Commons, but the Committee for Privileges and Elections decided in favour of Hamilton. Perhaps the most interesting disputed election was the by-election of 1759 following the elevation of William Scott (1893) to the Bench. The contestants were Alexander Stewart and William Hamilton (0947).Hamilton was initially elected and sworn on 15 February 1760, only to be declared not duly elected, and Alexander Stewart was sworn on 22 April; then Stewart was declared not duly elected and Hamilton was reinstated and sworn on 8 May. Both MPs petitioned parliament alleging bribery etc.257 Parliament was prorogued on 17 May. Hamilton died on 15 August. However, this parliament never met again, as the king died on 30 November and parliament was automatically dissolved.
Eighteen MPs - an unusually large number - represented the city between 1692 and 1800. They varied considerably, and included Bartholomew van Homrigh (2139), the Dutch Commissary General of William III's Irish army, David Cairnes (0335), who assisted in the defence of the city at the beginning of the century, Francis Andrews (0040), the Provost of Dublin University in the middle of the century,James Alexander (0029), the returned nabob, who carefully built up an interest in the corporation, Sir Andrew Ferguson (0724), who was mayor in 1798, and Sir George Fitzgerald Hill (1017), Recorder since 1791, who resigned and was returned for the county following the death of the Marquess of Waterford (0113) in 1800. Londonderry retained one seat after the Union, and Hill's resignation left the city seat free for Henry Alexander (0028), who in 1802 was returned for Old Sarum, while Hill reverted to sitting for the city. Eventually Hill became Governor of Trinidad, while Alexander accompanied his cousin, the 2nd Earl of Caledon (0027), to the Cape of Good Hope.