A painter, illuminator and sculptor, Master Bertram was probably from Minden in Westphalia. He lived and worked in Hamburg where he established a flourishing and prosperous workshop that employed a large number of assistants and received numerous commissions. Master Bertram visited Lübeck in 1375 and made a trip to Rome around 1390, which did not, however, influence his style. He also seems to have travelled to the Holy Land. His style is characterised by a smooth modelling of the draperies and the figures, which are, however, solid and heavy in a manner recalling Master Theodoric of Prague and which has led to the suggestion that Master Bertram trained in Bohemia. This artist was an important figure due to the influence of his style and oeuvre on subsequent generations of painters in northern Germany and particularly in Hamburg. The earliest work attributed to him consists of three miniatures in a missal (Pierpont Morgan Library, New York). Master Bertram’s masterpiece is the Grabow Altarpiece, originally in the church of Saint Peter in Hamburg, completed in 1383. Combining painting and sculpture, it has been a key element in establishing this artist’s oeuvre. Among the panels now attributed to Master Bertram is the triptych in the Hamburg Kunsthalle, painted for the monastery at Buxtehude and typical of the artist’s late style. Master Bertram died in Hamburg between February 1414 and May 1415.

Works