This article argues that medieval Arabic texts that were published in colonial northern Africa constitute as much a part of the history of colonialism and its legacy as that of the medieval centuries in which they were written. Using the publication history of a medieval Ibadi text and its French translations, I demonstrate how texts like it were edited, translated, and published not only for academic purposes, but also as contributions to the production of ‘useful’ colonial knowledge in Algeria. I begin with the first translation, published in 1878 alongside other ethnographic and historical studies funded by the colonial state. I then turn to the second translation, serially published between 1960–2 as its editors abandoned the country at the violent end of the colonial period. Finally, I address the Arabic editions published after independence, which recast it within a nationalist framework. Overall, I argue for the importance of addressing the colonial pasts of medieval texts in northern Africa.