English historian of modern diplomacy, and one of the first writers in English on German history from the 18th century.

During a brief political career Gooch specialized in foreign affairs and criticized the policy that led to the South African War. He was a Liberal member of Parliament from 1906 to 1910. Although a dedicated academician, he devoted much of his time to popular lecturing, and from 1911 until 1960 he edited the Contemporary Review, a monthly publication dealing with world affairs. He also contributed several chapters to the Cambridge Modern History. In the classic History and Historians in the Nineteenth Century (1913), he dissociated himself from the widely held view that history is a mere science.

Gooch also wrote Germany and the French Revolution (1920), Franco-German Relations, 1871–1914 (1923), English Democratic Ideas in the Seventeenth Century (1927), Courts and Cabinets (1944), Maria Theresa and Other Studies (1951), and The Second Empire (1960), among other books. He was joint editor of the Cambridge History of British Foreign Policy (1922–23) and British Documents on the Origins of the War, 1898–1914 (1926–38).