From the founding of Fort-Dauphin in 1643 to the abolition of slavery in the French territories in 1848, colonial and para-colonial architecture in Madagascar and the Mascarene Islands included the largest and costliest buildings in France’s premodern empire. This unique architecture was shaped by changing ideas of French identity, familiar imperial architectural and urbanistic forms, deliberately eclectic and cosmopolitan patronage, the exceptional ethnic diversity of the colony’s builders, and the fragile boundary between bondage and freedom that lay at the heart of French colonialism in the southern Indian Ocean. From modest projects that express a longing for French village life to classical baroque public buildings in the style of the Sun King and spacious private houses increasingly adapted to the local environment, architecture in Madagascar and the Mascarenes reflected a unique mix of metropolitan, colonial, and Indian and Malagasy forms and traditions. But buildings tell only half the story. There were many more builders in Île-de-France and Bourbon compared with other colonies, from a far greater variety of backgrounds – indentured Indian and French labourers as well as enslaved and free Malagasy, East African, and Indian people, including mixed-race engagé builders who operated within networks that predated the French presence. The stories of the carpenters, masons, engineers, and other skilled labourers who constructed the citadels, churches, and plantation houses are painstakingly reconstructed from primary documents that hold a wealth of information about daily life in the colonies. Encompassing over two centuries of urban, royal, and vernacular building, Architecture and Slavery in the French Indian Ocean complicates our understanding of slavery, race, and colonial architecture in the early modern period.