IN as far as we rely on van Mander's account we enjoy the advantage of a fairly informative biography of Jan Mostaert. It was at Haarlem in particular that van Mander pursued his investigations with such zeal, where in many of the houses he was shown pictures by 'old Masters' and where he came upon a living tradition relating to Mostaert. As long as that painter's activity remained attached to Haarlem, van Mander's account is reliable. In his Life of Ouwater van Mander refers to an honest old man, the painter Aelbert Simonsz, who in 1604 claimed to have been, some sixty years previously, that is in 1544, a pupil of Jan Mostaert at the time about seventy years of age. In his biography of Mostaert van Mander says that the painter died at a ripe old age about 1555 or 1556. Two documents published by Van der Willigen1, which have been much neglected of late, confirm these dates. As early as 1500 Mostaert received a commission for a painting at Haarlem, which means that at that time he was already working there as master. He left the city 'where he had been living until then' at an advanced age. Probably most of van Mander's information came from the lips of Mostaert's pupil Simonsz--that is from a good source. In his valuable contribution to the life of Geertgen, this witness makes the assertion that Mostaert (although he was born as early as c. 1475) never met Geertgen, from which we can deduce that he would certainly have known Geertgen if the latter had lived long enough. It would thus seem that not only was Mostaert born in Haarlem, not only did he live and teach there towards the end of his life (about 1546) but he was also trained there. He must therefore have been closely linked to the Haarlem art tradition. This is supported by the information that when still very young he was a pupil of Jacob of Haarlem, who executed the 'Zakkedragers' (corn carriers) altarpiece for the great church there. We have no further information about this Jacob unless we venture to assume that he is identical with an anonymous painter who stands, stylistically, between Geertgen and Mostaert.
Van Mander speaks very highly of the refined habits and the courtesy of Mostaert who, he says, was the descendant of an old and noble family. A period of activity at court interrupts like an episode the long years of____________________