Jan Maertz Engelsman (1593 in Hoorn – 1654 in Alkmaar), was a Dutch Golden Age painter and member of the Hoorn city council.
According to Houbraken he was a glasspainter who taught Josef Oostfries.
[2] He is mentioned in Theodorus Velius' Chronyk van Hoorn.
Stained glass windows by him are registered in Alkmaar, Zuid-Schermer, Broek in Waterland, and Etershem.
[3] According to the RKD he was a glasspainter who signed his works "IME".