Philippe Costamagna is a respected art historian of substantial accomplishments. Since 2001 he has served as the Director of the Musée des Beaux-Arts in Ajaccio, Corsica, that remarkable repository of what remains from Cardinal Joseph Fesch’s original collection of more than sixteen thousand paintings and works of art. The prelate enjoyed the distinct benefits of being Napoleon Bonaparte’s uncle and may have been one of history’s most acquisitive—if perhaps not one of its most fastidious—collectors. Though much of the collection was dispersed at the end of the Empire, a core group of almost one thousand works is still in Corsica, divided between the Ajaccio museum and other minor local institutions. Costamagna has carefully culled and catalogued these holdings, illuminating—among others—several surprising items such as a key work by the exceedingly rare Ferrarese artist Cosmè Tura, an impressive early Botticelli, and a prototypical example of French Baroque classicism by Nicolas Poussin. Costamagna has also published a definitive Jacopo Pontormo catalogue raisonné as well as extensive and valuable research on that great artist’s lesser-known followers and imitators. The art-historical coup that gained the widest notoriety for the French scholar, however, was the discovery in 2005 of a spectacular Christ on the Crossby the Florentine sixteenth-century master Agnolo Bronzino. The monumental work, commissioned by one of that city’s most prominent families, the Panciatichi, was the subject of lavish praise by Vasari but had languished unrecognized for centuries in a church in Nice—by a felicitous coincidence, not far from where