The record of Herrmann's marriage to Rosalie names his parents.

His children up to Johanna (born March 1891) were born in Beuthen. From Henriette (born August 1892) they were born in Breslau. This, and his date of birth given in the 1939 census, confirm he is the Hermann Nothmann born 17/09/1864 in Beuthen, died 16/05/1940 in Breslau listed in the Reichsvereinigung der Juden in Deutschland (RvD) Card File.

In the 1939 census, Herrmann is living in Breslau with Charlotte Nothmann geb. Nebel born 02/06/1876 in Sohrau. I speculate that his first wife, Rosalie geb. Nebel, died giving birth to their daughter Rosalie (born 1902) and Herrmann subsequently married Charlotte, probably a close relative of Rosalie.

A tree in JewishGen's "A Family Tree of the Jewish People" project shows Georg and Artur as sons of Herrmann Nothmann and Charlotte Nebel; however, the Breslau synagogue community address list (ca 1930) shows Georg and Artur living with Heinrich Nothmann and Rosa geb. Urbainczyk at Augustastrasse 186. Heinrich and Rosa later moved to Sonnenstrasse 36. At the time of the 1939 census Herrmann and Charlotte lived at Sonnenstrasse 42 while Herrmann's daughter Rosalie lived at Sonnenstrasse 38, so it is tempting to speculate that there was a close connection between Heinrich and Herrmann.