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,
George III of the United Kingdom Prime Minister. After a brief illness, which may have presaged his illnesses to come, George settled on Lord Rockingham to form a ministry, and dismissed Grenville. Lord Rockingham, with the support of Pitt and the King, repealed Grenville's unpopular Stamp Act, but his government was weak and he was replaced in 1766 by Pitt, whom George created Earl of Chatham. The actions of Lord Chatham and George III in repealing the Act were so popular in America that statues of them both were erected in New York City. Lord Chatham fell ill in 1767, and the Duke of Grafton took