The Aix Annunciation Triptych (1443–1444) is attributed to Barthélemy d’Eyck and is widely celebrated as a masterpiece of fifteenth-century Western European painting. Based on an in- depth study of the altarpiece, this book offers a more complete picture of the artist’s artistic origins, career, workshop practice, and professional network. Combining art-historical, archival, and technical approaches, this study brings together newly discovered documents and provides a reappraisal of the patron and the liturgical context of the work. Furthermore, it places the Aix Annunciation Triptych within the broader landscape of fifteenth-century Provençal altarpieces and presents the results of a material and technical analysis conducted on the surviving fragments. These findings resolve long-standing questions regarding the work’s original format and significantly deepen our understanding of Barthélemy’s artistic training and methods.