In his critical exhibition catalogue of Early Flemish Masters in Bruges in 1902, the Ghent great connoisseur of early Flemish Art and art historian Georges Hulin de Loo, came to the conclusion that Isenbrandt was actually the anonymous "Master of the Seven Sorrows of the Virgin" and the author of a large body of paintings previously attributed to Gerard David and Jan Mostaert by the German art historian Gustav Friedrich Waagen. He is therefore sometimes called the Pseudo-Mostaert. Even if this attribution to Isenbrandt cannot be proven without doubt, it is now generally accepted by some art historians, although many others regard Isenbrandt as a convenient label for a body of work by many different artists.