Some authorities have proposed, on stylistic grounds as well as the likely family relationship, that Barthélemy trained in the workshop of Jan van Eyck, and worked in the 1430s on the Milan-Turin Hours, a famous and important illuminated manuscript, where a number of different painting "hands" have been distinguished. Much of this only survives in black-and-white photographs after its destruction in a fire in 1904. A painter called only "Barthélemy" is documented as working in Dijon for Philip the Good, Duke of Burgundy in 1440; this may well be him. René of Anjou, who was to become Barthélemy's major patron, had been held prisoner there by Philip. By 1444 Barthélemy d'Eyck was in Aix-en-Provence in the South of France presumably working with the leading French painter Enguerrand Quarton as they witnessed a legal document together.