Siegfried Loewenthal was born on August 18, 1874 in Heiligenstadt, Thuringia, Eichsfeld district, as the son of the banker Louis Levy Loewenthal and his wife Regina, née Mosheim.
He studied law in Erlangen and received his doctorate there. In Magdeburg he rose from assessor to presidential judge from 1902 and was regional court president in Oels/Lower Silesia from 1922 to 1927. In 1933 Dr. Siegfried Loewenthal was forced into retirement and banned from working.
From 1934 until his death in 1951, Siegfried Loewenthal lived at Bergengruenstrasse 57, then Lagardestrasse. He was able to survive the Nazi era with the help of his family and friends. He probably lived in a privileged mixed marriage. He was known to provide legal advice to fellow Jews. From 1933 to 1945 he is said to have given free advice to those persecuted by the National Socialist regime. The Jewish Lachmann family also lived at Bergengruenstrasse 57, a semi-detached house.
After the war, Siegfried Loewenthal was a sought-after specialist. He was appointed to the Berlin city council by the Allied Command. In August 1945 he became chief president of Regional Court II, after 1949 for West Berlin.
Dr. Siegfried Loewenthal died on March 18, 1951 in Berlin.
See also: https://de.wikipedia.org/wiki/Siegfried_Loewenthal_(Jurist)