In Year 2 of the Revolution (1794) Robespierre, seeking to establish a new deist national morality created the Festival of the Supreme Being celebrated on 20 Prairial Year 2 (8 June 1794). This book begins by tracing the progress in the development of Robespierre’s thinking on the importance of the problem which the lack of any acceptable national moral system through the early years of the Revolution had created, his vision of a new attitude towards religion and morality, and why he chose a Revolutionary Festival to launch his idea. It focusses on the importance of the Festival by showing that it was not only a major event in Paris, with a huge man-made mountain on the Champ de Mars; it was also celebrated in great depth in almost every city, town and village throughout France. It seeks to redefine the importance of the Festival in the history of the Revolution, not, as historians have traditionally dismissed it, merely as the performance of a sterile and compulsory political duty, but on the contrary, as a massively popular national event. The author uses source material from national and local archives describing the celebrations as well as the reaction to the event and its importance by contemporary commentators. This is the first book since the 1980s and the only work in English to focus on this Festival and to redefine its importance in the development of the Revolution.