Martin Aufhäuser came from a banking family based in Munich, where the Aufhäuser bank was established in 1870. The family was Jewish, and after 1933 lost their property to the Nazis. Martin was briefly detained at the Dachau concentration camp, but released in 1939 after which he moved to the Netherlands. His collection of almost 40 paintings was seized by the Nazis. However, he managed to bring his important print collection to the Netherlands, and sold it, via his son Walter then living in Montreal, to American collector Lessing Rosenwald.
Field, Richard S. Fifteenth Century Woodcuts and Metalcuts. Washington, 1965: preface
Rosenwald, Lessing J. Recollections of a Collector, Jenkintown, Pa, 1976: 14-18.
Boyes, Roger. "Family's Nazi past thwarts art claim." London Times: 2 February 1999:11