After a short professional career in banking and industry, he studied economics in Paris, Vienna and Tübingen, where he finished his studies and wrote a thesis about Bolshevism in 1919.
He was an Austrian-German economist and attorney-in-fact of the Rotterdamse Bank who spent a part of his life in the Netherlands. He was also an art collector. In the same year, he moved to the Netherlands.
From 1929 until 1944 he lived in Amsterdam.
Mautner never married and had no children. During the war Mautner attempted unsuccessfully to escape from the Nazi regime.
In December 1943 Mautner was removed from his home in Amsterdam during a raid and transported to Westerbork transit camp and from there to Theresienstadt concentration camp. Mautner died on or around 29 September 1944 in Auschwitz concentration camp.
Mautner collected paintings.
His collection also included some Dutch masters. He continued purchasing works of art during the war. From 1941, he was no longer able to do so in his own name because of his Jewish origins.
He gave works of art to various people for safekeeping.
In February 1942, Mautner was ordered to move to Tugelaweg in Amsterdam as a result of the forced relocation of Jews. He sent 15 paintings for safe-keeping with the collector Doctor J. van Dongen on the city"s Museumplein.
The latter kept all of these items until after the war. Other works, including a Brueghel and a Timmermann, were sold under duress in 1943 by Mautner.
Various of Mautner"s works of art and other possessions were recovered for his heirs, by custodians of his estate after the war.
The 15 paintings in Judge-Advocate van Dongen"s custody were probably bought by van Dongen with the consent of Mautner"s heirs. Three of the paintings that Mautner sold under duress are:
P. Brueghel II, A Tax Collector" General’ s Office, 17th century NK 2297
F. Timmermann, The Beheading of Saint John the Baptist, dated 1534 NK 1655
J.H. Steen, River landscape with figures and a wagon in front of a tower, third quarter 17th century NK 2655
The latter two were acquired by the Sonderauftrag Linz and returned to the Netherlands after the war, where they became part of the NK-Collection of the Stichting Nederlands Kunstbezit. He also sold 12 paintings, primarily 19th century, to West. Kadzik from Vienna.
lieutenant is unknown where the works are.