The first Prime Minister of the United Kingdom was Sir Robert Walpole, serving from 1721 to 1742. Often regarded as the de facto first prime minister, Walpole held the position of First Lord of the Treasury and led the government in the House of Commons. His tenure is marked by a significant consolidation of power within the executive branch and the establishment of precedents for the modern parliamentary system. Walpole's leadership favored stability and economic growth, amidst a backdrop of political and social change. His influence shaped the role of future prime ministers and the evolution of British politics, enduring as a pivotal figure in history.