No estimates of the total electorate in this constituency survive, but there were 60 freemen in the principal borough in 1685, and it is reasonable to suppose that none of the four contributory boroughs exceeded this figure. The charter of 1284 provided that the constable of Caernarvon Castle, who was appointed by the crown, should also act as mayor during his term of office. Since he seems to have functioned as returning officer, this gave a potential interest to the Robartes family, constables from 1663 to 1713. No disputes over the franchise or contested elections are known in this period, despite the restricted parliamentary opportunities afforded to the Caernarvonshire gentry while the county seat was in the hands of the Bulkeleys from 1675 to 1687. William Griffith, a hard-drinking Cavalier, intended to stand at the general election of 1660, but was probably deterred by the qualifications imposed by the Long Parliament. William Glynne was returned, of whom the indenture says all that can be said by describing him as the son of Serjeant John Glynne, the eminent lawyer who was sitting for the county. With their Presbyterian and parliamentarian record, they were both replaced in 1661. The borough seat was taken by Griffith by agreement with Sir Richard Wynn, who was returned for the county. Apart from securing the transfer of the sessions from Conway to Caernarvon in 1663, he was not an active Member and is unlikely to have contested the exclusion elections. Caernarvonshire was represented in these Parliaments by an exclusionist, Thomas Mostyn, the heir to a great estate in Flintshire, who had taken up residence in the county. He gave way to Griffith’s son John in James II’s Parliament. Both father and son died later in the reign, but at the general election of 1689 another Tory, Sir Robert Owen, was successful.

Trans. Caern. Hist. Soc. vii. 27; viii. 46; Cal. Wynn Pprs. 355, 361, 362, 374.