Walther Löwenstein was the son of master butcher Salomon Löwenstein and his wife Bertha, née Hope. The parents were members of the Jewish community. The family lived for many years at Märtmannstr. 40.
Workwise, Walther Löwenstein followed in his father’s footsteps, later taking over the family butcher’s shop and also his parents’ home.

Walther Löwenstein married his non-Jewish wife Johanna, née Viets, on 10 February 1931 in Aplerbeck. The marriage produced a daughter, Lotte, who was born in Aplerbeck in January 1932.
As Walther Löwenstein was living in a so-called “privileged mixed marriage” with a non-Jewish spouse, he was protected for a long time from the worst of the Nazi persecution.

In 1939, however, his butcher’s shop was closed, and he was required to do forced labour in road construction.
Towards the end of September 1944, all male Jews still living in “privileged mixed marriages” in Dortmund were arrested by the Gestapo and taken on 29 September to a work camp in Weissenfels. There, the deportees were forced to do slave labour for chemical and hydrogenation plants engaged in the production of vehicle fuel.

In February, they were deported to Theresienstadt. Walther Löwenstein arrived there on 12 February 1945 with other Jews from Dortmund on Transport XVI/6 from Leipzig, and experienced the liberation in May 1945; however, he was unable to return to Dortmund.

A man and a woman from Dortmund, who had also been deported to Theresienstadt, testified that Walther Löwenstein died of epidemic typhus in the Theresienstadt ghetto after it had been liberated. However, the witnesses were not able to date the death precisely, so Walther Löwenstein was officially declared dead with effect as of 31 May 1945.