Co. Waterford in 1692 was under the influence of Charles, 3rd Earl of Cork and 2nd Earl of Burlington, a great-grandson of the 1st (great) Earl of Cork. He died in 1703 and was succeeded by his eight-year-old son Richard, 4th Earl of Cork and 3rd Earl of Burlington - usually known as Lord Burlington - who gave nominal attention to his property, much of which he sold to finance his predilection for the arts. He died in 1753, preceding by a year his only daughter and heir, Charlotte, Marchioness of Hartington, to whom the still extensive Boyle lands in Co. Waterford and Co. Cork devolved. In 1748 Lady Charlotte Boyle had married the 4th Duke of Devonshire, then Marquess of Hartington. The Dowager Countess of Burlington paid considerable attention to her grandchildren's Irish inheritance, but she died in 1758. The 4th Duke was an important figure in the government of the day, which was involved in fighting the Seven Years' War. He died in 1764, leaving his heir, the 5th Duke, a minor. The 5th Duke was by nature lethargic and left the management of his Irish political influence to a distant relative, the Earl of Shannon, and to his cousins the Ponsonbys.
This left a political vacuum in Co. Waterford which was filled by the Beresfords, Earls of Tyrone and Marquesses of Waterford, who lived in the county at Curraghmore. In 1785 Co. Waterford was described as 'well governed. Almost entirely under Lord Tyrone's (0113) influence. There have been recently many attempts of the popular party.'390 The marquess's able brother, John Beresford, represented the county from 1761 until his death in November 1805. Beresford was said to have no property in the county - his estates were in the north, and he had only a small freehold in Co. Waterford worth less than £100 p.a., given to him by his brother, the marquess. The Beresford interest did have opposition: apart from the Ponsonbys representing the sleeping interest of the Duke of Devonshire, there was the Villiers family, later Villiers-Stuarts, of Dromana, a constant presence throughout the century but hampered by various family vicissitudes. In 1730-33 one of the family, James Fitzgerald-Villiers (Lord Villiers), sat for the county, while in 1790 'Lord Grandison contested this County with Lord Waterford (0113) and lost it.'391 Grandison was the only surviving son of Aland Mason and Lady Elizabeth Villiers, suo iure Countess of Grandison.392 By the end of the century the Beresfords and the Ponsonbys had come to an agreement whereby each returned an MP, which made everything 'easy and inexpensive'. But the 1st Marquess died in 1800 and his inexperienced son, the 2nd Marquess, decided to end the agreement as he thought he could control the entire county. However, the Devonshires' interest in their neglected Irish inheritance increased after the Union had made it a Westminster interest.
Waterford had a county borough (Waterford city) and three parliamentary boroughs (Dungarvan, Lismore and Tallow). All the parliamentary boroughs had originally been under the influence of the Earls of Cork. Dungarvan survived the Union. The county electorate was probably about 700 in 1768: the gross poll was 594. By 1815 it had risen to about 3,300.