This is one of a group of small devotional panels of the composition, of which examples include those in the National Gallery, London and the Louvre, Paris, and discussed most recently in detail by Lorne Campbell (National Gallery Catalogues. The Fifteenth Century Netherlandish Paintings, London, 1998, pp. 63-6); for the most complete list, see H. Adhémar, Les Primitifs Flamands, I, Corpus, etc., 5, Le Musée National du Louvre, pp. 57-8. The panels of the Virgin were, as in the London and Paris versions, originally the left wings of diptychs, the right wing depicting Christ crowned with Thorns: the pairing of the sorrowing Virgin and Christ being a fairly common one (for which, see E. Panofsky, ''Imago Pietatis'. Ein Beitrag zur Typengeschichte des 'Schmerzenmanns' und der 'Maria Mediatrix'', in Festschrift für Max J. Friedländer zum 60. Geburtstage, Leipzig, 1927, pp. 261-308), although as noted by Campbell (op. cit., p. 63) it was less usual to pair a Mater Dolorosa with an image of Christ before the Crucifixion.
The type of the Mater Dolorosa probably derives from Rogier van der Weyden, who had depicted similar Virgins, for example in the Beaune Last Judgement (1443-51; Beaune, Musée de l'Hôtel-Dieu) and the Triptych of Jean Braque (c. 1452-3; Louvre, Paris), that were then popularised by his contemporaries and followers. The present composition was itself in the past given to Rogier and his school, but was reclassified as Bouts by Friedländer (Die altniederländische Malerei, III, Berlin and Leiden, 1925, p. 124), who suggested that the London panels were from his workshop and listed a further eight versions of either the diptych or the Virgin alone.
In his supplemental volume (XIV, 1937, p. 91), Friedländer suggested that an additional panel in the collection of Baron van der Elst (now Chicago, Art Institute) may be the prototype by Bouts, but dendrochronological evidence has shown that it is likely to have been painted after his death (P. Klein, 'Dendrochronological Findings of the Van Eyck-Christus-Bouts Group', in M. Ainsworth, ed., Petrus Christus in Renaissance Bruges: an interdisciplinary approach, New York and Turnhout, 1995, pp. 156-7). In the continuing absence of any other candidate, it therefore seems likely - as first suggested by Wolfgang Schöne (Dieric Bouts und seine Schule, Berlin and Leipzig, 1938, p. 133) - that the originals (for which Schöne suggested a date of circa 1450) are lost, and that the known versions of the composition are by Bouts' workshop or followers.