Stefan Ferdinand Schminghoff was the son of a miner, Theodor Schminghoff, and his wife Maria, née Nordicker. The family lived in Brambauer in House No. 79 – street names had not yet been introduced there. Later, the family lived at Waltroper Strasse 54, then at Waltroper Strasse 128.

In 1916, Stefan Schminghoff went to live at Evinger Strasse 15 in Dortmund. At this time, he was already married to Ottilie Böhm (born 6.1.1891).

It is confirmed from the principal archive of the coalmining company Ruhrkohle AG that, at least for a short time, Stefan Schminghoff was employed as a faceworker at the Zeche Kaiserstuhl II mine in Dortmund. Later, Stefan and Ottilie Schminghoff lived at Kurfürstenstrasse 32 in der north of Dortmund.

Only little is known about the persecution and arrest of Stefan Schminghoff. He had already been the subject of prosection on account of his homosexuality and offences against Section 175, the law prohibiting sexual acts between men, and had already served a prison sentence in Münster in 1928/29. On 12 June 1940, he was sent to Sachsenhausen concentration camp, where he was given prisoner number 25236.

Stefan Schminghoff’s name also appears on the so-called “Büge List”. Emil Büge was a prisoner who was assigned to duties in the clerical office of Sachsenhausen concentration camp. He kept lists with the names of prisoners incarcerated under Section 175 who were murdered in the concentration camp. According to these records by Emil Büge, around 600 homosexual men were murdered in Sachsenhausen during the period from 1940 to 1943 alone.

Stefan Schminghoff was murdered in Sachsenhausen concentration camp on 19 July 1940. The death certificate states the cause of his death as chronic inflammation of the kidneys. The urn with his ashes was buried in a collective grave at Schönfelder Allee in Berlin-Altglienicke.