In 1904 his artistic identity was first established, based on a group of works signed with the monogram ‘I.S.’. Opinions vary as to whether he was originally a German, Baltic or a Dutch-born painter, but the consensus is that he worked in Leiden in the 1630s, as his refined, articulated brushwork, his subject-matter and his almost scientific realism reflect the influence of the then relatively unknown work of the young Rembrandt (1606–69) and other painters in his milieu, notably, the Leiden Fijnschilder Gerrit Dou (1613–75). The earliest work by the Monogrammist I.S. is dated 1632, two years after Rembrandt’s departure for Amsterdam. David de Witt, chief curator at the Museum het Rembrandthuis in Amsterdam, proposes that the Monogrammist I.S. was Dutch but travelled east via Scandinavia. His known oeuvre consists exclusively of portrayals of single figures, either ‘tronies’ or actual portraits.
Books on the Monogrammist I.S.
Arthur Wheelock, ‘Making Faces: The Development of the Tronie in Seventeenth-Century Leiden’ in Anonymous Portraits: Dutch Seventeenth-Century Tronies, New York, 2019.
Leon Krempel, Marlene Dumas: Tronies, Düsseldorf, 2010.
Werner Sumowski, Gemälde der Rembrandt Schüler, vol. IV, Landua/Pfalz, 1983.
Theodor von Frimmel, ‘Von Monogrammisten IS’, Blatten für Gemäldekunde, 1904.