Lord Lansdowne (1845-1927) was one of the last hereditary aristocrats to wield power by virtue of his birth--and he used it to establish himself as a force to be reckoned with in politics for half a century. This biography, the first to be written with full access to Lansdowne's extensive archive, presents the man and politician in the context of his era, offering not only insight into his own life and achievements but also fascinating details about his interactions with the leading personalities and events of his day. Simon Kerry deftly traces the long arc of Lansdowne's career, which included service as Governor-General of Canada, Viceroy of India, Secretary of State for War, Foreign Secretary, and Leader of the House of Lords. The Lansdowne we meet in these pages is a moderate progressive, honest and courteous to the last, trusted by everyone, and struggling--as did so many of his class and generation--with the decline of British power that followed the end of World War I. ​A remarkable achievement, Lansdowne will stand as the definitive biography of a statesman who played a major role at a pivotal moment in the history of the United Kingdom.