[4] He is thought by many to be the Master of the Shadows responsible for parts of the calendar of the Très Riches Heures du Duc de Berry.
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.
Together with a fine portrait dated 1456 (Lichtenstein Collection, Vienna), and a fragment with a small crucified Christ in the Louvre, this is the only surviving panel painting associated with him; most of his later works are illuminated manuscripts commissioned by René of Anjou.
René of Anjou was a prince of the Valois family who had a complicated range of titles and claims, including that of King of Naples, from which kingdom he was ejected by the House of Trastámara by 1442.
Harthan suggests the designs for these may have been sketched by René himself for Barthélemy to execute: "the faithful interpreter of the King's exalted ideas, an inseparable, discreet companion and the effective partner, perhaps, in joint artistic enterprises"[7] [1].
The two best-known manuscripts are the Livre du cueur d'amour esprit and the Théséide, both in Vienna (Österreichische Nationalbibliothek, Codex 2597, 2617), dating from 1460 to 1470, with sixteen and seven miniatures respectively.
His exceptional skill at lighting effects is fully deployed; four of the sixteen miniatures are night scenes, and others show dawn or dusk with great brilliance.
[8] He is also believed by many art historians to be the Master of the Shadows who added to the illustration of the Très Riches Heures du Duc de Berry in the mid 15th century, long after the Limbourg brothers had produced the most famous miniatures (they and the Duke died in 1416, leaving the manuscript unfinished and unbound).
Only these calendar scenes, and possibly the faces in the double-page Procession of St Gregory (Walther & Wolf, op cit), show his style; many other miniatures were added a generation later by Jean Colombe.