The portrait of Isabella of Portugal, Duchess of Burgundy, in the J. Paul Getty Museum

The authorship of the portrait of Isabella of Portugal in the J. Paul Getty Museum, Los Angeles, is discussed. At its sale in 1883, this painting was attributed to Jan van Eyck, but since 1979 it has generally been regarded as a copy after a lost original by Rogier van der Weyden; it closely resembles a portrait of Isabella in a lost altarpiece painted by the artist and sent, maybe in 1445, to the monastery of Batalha, Portugal. It is painted on a panel made in or after 1451 by a carpenter who supplied Van der Weyden's workshop. It seems possible that this painting was by an artist who was active in Van der Weyden's workshop, using the master's designs and some of his methods of composition. By 1523–24, and probably by 1516, it or a very similar version was in the collection of Margaret of Austria, and probably soon after 1524, it was transformed by a skillful painter trained in the early Netherlandish tradition, who repainted Isabella's clothes. Perhaps in around 1600, an inscription was added, identifying Isabella as a Persian Sibyl, and seemingly also as the first of a series of sibyls.