William, 1st Earl of Chatham (1708–78); known as Pitt the Elder. As secretary of state (effectively prime minister), he headed coalition governments 1756–61 and 1766–68. He brought the Seven Years War to an end in 1763 and also masterminded the conquest of French possessions overseas.
William (1759–1806), prime minister 1783–1801 and 1804–06; the son of Pitt the Elder; known as Pitt the Younger. The youngest-ever prime minister, he introduced financial reforms to reduce the national debt.