After Emil Neumann's death in 1923, his son Ludwig became the sole owner. In addition to the core business papers such as reports, accounts, property papers and correspondence, there are also papers relating to the enforced sale including correspondence to, from and about Joseph Herbring, the new, non-Jewish owner in October 1938 [1023/2/13; 1023/2/15].

After the war Ludwig Neumann returned to Germany to reclaim what was rightfully his. The Essen branch of the firm along with most of Essen had been completely destroyed in the bombing during the war. He managed to secure a loan from his sister's frozen German bank account in order to re-establish the business in Germany in 1950. The business had fallen into difficulties and by 1949 was no longer functioning. Ludwig Neumann managed to obtain a work permit and remained for approximately 4 years in M.-Gladbach building up the company once more. Interestingly, in the third bundle of papers relating to Ludwig's time in Germany after the war there is a permit for a 'pistol for self-defence', dated 14 April 1951 [1023/1/37]. Whether this was obtained in response to a specific threat or as a general protection may be ascertained from the file of family correspondence [1023/1/38]. It is not clear what the fate of the company was after Ludwig's attempts to rejuvenate it. A letter dated September 1954, shortly after the death of his mother, Dina Neumann, states that they were trying to find a buyer for the machinery. It is probable therefore that the company was broken up and its assets sold off at about this time.

Emil Neumann, born in Hamerstein Provinz, West Prussia in 1861 and living in Essen at the time of his marriage in 1892, married Dina Stern from Felsberg, Hessen, born in 1868. Louis Stern, her brother also worked for the company. He died in 1932. Emil and Dina had 2 children, Ludwig (aka Lutz) born in 1896 and Luise (aka Liesel, aka Louise) born in 1893). Having served and been wounded during the First World War (for which he was decorated), he studied at the technical Institute for Textile Industries, Württemberg, 1919-1920, and became the sole owner of the company Neumann and Mendel and manager of the associated export firm of Schrey and Co. in 1923 after the death of his father. Luise worked as a nurse in the Friedrich Krupp Krankenhaus, Essen, throughout most of the war. In 1919 she married Richard Elkisch, a Jewish businessman born in Berlin. Hardly anything is known about the latter. Luise was forced to leave her Berlin flat, Kaiseralle 203, in 1938 [1023/1/39].

In 1938, having been forced to sell the company, Ludwig was interned in Dachau for a couple of months, and released on the understanding that he would leave the country immediately. On his arrival in Great Britain after a period of internment as an enemy alien, he held a number of posts as a production manager in the clothing industry before his return to Germany in 1950 to resume the management of the family business. There is a considerable amount of correspondence during this period between him and his sister. Luise and her mother came over at about the same time time and the family settled in Birkenhead where they remained. Dina died in 1954, Ludwig in 1970 and Luise in the 1980s. Since neither Ludwig nor Luise had any children the material is thought to have ended up with distant family members who deposited it at the Wiener Library.