Robert Campin
The panel seems to be the left-hand wing of a dismantled diptych, perhaps with the "Saint George and the Dragon" panel now in the National Gallery of Art, Washington, D.C. As an early van der Weyden, it takes influence from Robert Campin and Jan van Eyck. Van der Weyden served his apprenticeship under Campin, and the older master's style is noticeable in the architecture of the niche, the Virgin's facial type, her exposed breast and the treatment of her hair.