Taking as starting point an unrealized project for Conques by Jean- Camille Formigé, the architect of the abbey-church’s restorations in the 1870s–1880s, this paper explores the broader theories and practices of historicist restoration and building projects between the 1840s and the end of the nineteenth century. By looking firstly at the theorical frame in which the concepts of “Byzantine”, “Neo-Byzantine”, “Romano- Byzantine” and “Romanesque” were fabricated, and by then examining some of the most important monuments of historicist architecture (such as Saint-Front in Périgueux, the Sacré-Coeur), I aim to uncover the impact of these terms and their role in the reinvention of medieval art as well as in the formulation of racist, colonial, and national myths in modern art history. In these crucial years for the development of the discipline of art history but also for the formation of a French national identity, the role of the “Romano-Byzantine”and “Byzantine”styles reveals a tension at the intersection of religious revival, orientalist art history, and trans-Mediterranean – and perhaps also colonial – desires.