Using digital technology, this article offers new answers Daniel Mornet’s famous question «What did the French read before the Revolution?» Using accounting records, the author and his team created a database of the celebrated Swiss protestant publisher-wholesalers, the Sociététypographique de Neuchâtel (STN). This database allows us to trace the origins and sales destinations of over 450,000 copies of 3,600 different works around the STN’s Europe-wide client network and to describe the literary field of the late enlightenment. In the process, it provides rich comparative and representative insights into the international trade in French books and reading tastes across Europe. However, the STN archive does not give a complete picture of the francophone book market, despite the relative impunity with which it could trade in illegal and pirated works while operating from a Prussian-ruled Swiss base. Indeed, in terms of sheer numbers, the most important part of the pirate market was comprised of Catholic religious works, and these swamped the more notorious parts of the clandestine trade. Yet despite its significance, few traces of this trade survive in the classic studies of the enlightenment book trade.