Earl of Londonderry extinct on the death of his great-grandson, the fourth Earl, in 1714. The second creation came in 1726 in favour of the soldier and politician Thomas Pitt, 1st Baron Londonderry. He had already been created Baron Londonderry in 1719 and was made Viscount Gallen-Ridgeway at the same time as he was granted the earldom, also in the Peerage of Ireland. He was the husband of Lady Frances Ridgeway, daughter and heiress of the fourth Earl of the first creation. A member of the prominent Pitt family, he was the uncle of William Pitt, 1st Earl of Chatham. His younger son,
Earl of Wilton Thomas Egerton, 1st Earl of Wilton died in 1814, the Grey de Wilton barony became extinct as he had no male heirs, while the Grey Egerton baronetcy passed to his kinsman John Grey Egerton (1766–1825), who became the 8th Baronet. The titles of "Earl of Wilton" and "Viscount Grey de Wilton" passed, according to the special remainder, to the 1st Earl's grandson Thomas Grosvenor (1799–1882), who adopted the surname of Egerton and became the 2nd Earl. He was the second son of Lady Eleanor and the first Marquess of Westminster, the younger brother of Richard Grosvenor, 2nd Marquess of Westminster