Pitt was the son of a member of Parliament and the grandson of Thomas Pitt who had helped to build British trade in India. He entered Parliament in 1735 at the age of 27 after attending Oxford. He gained attention by leading the Patriot faction in opposition to prime minister Sir Robert Walpole, but his skills at oratory did not establish for him a power base. His first office was as paymaster-general,1746, where he made a name for himself by his honesty and failure to take financial advantage of the office. Discouraged by his lack of progress within government, he turned to criticizing the Duke of Newcastle, and his government's war policy, resulting in his dismissal in 1755. After Newcastle resigned in 1756, Pitt formed a government with George Grenville and the Duke of Devonshire. Pitt and Grenville argued over the administration of the war and in April, 1757, King George II dismissed Pitt. After several months with virtually no government, Pitt was recalled to government at the outbreak of the Seven Years' War to form a coalition government with Newcastle.
Pitt served very effectively as a wartime prime minister with Newcastle attending to domestic affairs. He sent a strengthened British fleet to blockade French ports and provided supplies to Frederick the Great of Prussia. His policies resulted in victory over the French in India and Canada and on the seas. He sought to continue the war until France was completely defeated, and broaden the war by declaring against Spain. He met with opposition by other ministers and disagreement by George III. He resigned in 1761 and spent the next five years criticizing the government. He called the 1763 Peace of Paris