This article traces the fl uctuating relations that have existed between the Société des études Robespierristes, which is now celebrating its centenary, with the younger International Committee of Historical Sciences, created in the years after 1920 against the backcloth of a historical, community still broken and divided by the First World War and its aftermath. The Committee saw itself as having a missionary function and sought to bring together historians of countries divided by politics and ideology. How should the Robespierristes respond? The evidence of the pages of the AHRF and those of successive Bulletins of the Committee suggest that relations were often strained, even though the historians who contributed on revolutionary themes to the work of the World Historical Congresses were often themselves members of the Society. During a lengthy period - especially after 1940 - historians of the revolution appeared less frequently at these Congresses, until, from around 1960, they made a renewed effort to seek affiliation. This proved a lengthy frustrating experience, until in 1975, at San Francisco, an affi liated commission on the French Revolution was admitted. Since then that Commission has considerably evolved, without losing its close association with the Society.