British historian Arnold J. Toynbee (1889–1975) was a research professor of international history at the London School of Economics and director of studies at the Royal Institute of International Affairs. A remarkably prolific writer whose works were translated into some thirty languages, he is best known for his 12-volume A Study of History, which put forward a theory of history based on an analysis of the growth and decline of civilizations. He is regarded as one of the most influential scholars and public intellectuals of his time and a leading specialist in international affairs.