Leopold Singer was born as a son of the Jewish merchant Wilhelm Singer and his wife Rosalie, née Klein in Vienna in 1869. After studying technical chemistry in Vienna, Zurich and Karlsruhe, Singer was awarded his doctorate in philosophy in 1892 with a thesis on the theory of petroleum formation (Beiträge zur Theorie der Petroleumbildung). He then worked at his father’s oil refinery in Orșova in what is now Romania. In 1897, he married Jenny Beck, with whom he had two sons, Erwin and Otto. From 1903 to 1912, Singer was the director of the Aktien-Gesellschaft für Mineralölindustrie formerly called David Fanto & Co. in Pardubice in what is now the Czech Republic. Another stage in his professional career was the position of managing director at the Mineralölwerke Rhenania AG of the Royal Dutch Shell Group in Düsseldorf which he held from 1914. This was followed by positions as a consultant for the Allgemeine Depositenbank in Vienna (1918) and the Universal Oil Co. of Chicago (1926). From 1909, he was also a permanent contributor to the journal Petroleum. Furthermore, he translated specialised literature from English and worked on the multi-volume standard work on petroleum Das Erdöl, seine Physik, Chemie, Geologie, Technologie und sein Wirtschaftsbetrieb, edited by Carl Engler and Hans von Höfer. Finally, Leopold Singer held dozens of patents in the field of distillation technology. After the "Anschluss" (annexation of Austria to the Nazi German Reich), the Singer couple, who had lived at Grillparzerstraße 7/3 in Vienna’s 1st district, since 1919, were subjected to repression by the Nazi regime due to their Jewish origins. In his property declaration of July 1938, Singer estimated his library to be worth the sum of RM 8,000. In 1939, the couple moved to Romania. It remains unclear how and when they reached Great Britain, where Leopold Singer died in London in 1942. The elder son Erwin had already died in Vienna in 1936. Otto emigrated to Shanghai in 1938 and subsequently lived in Australia and the USA. He died in 1981.

In the course of systematic provenance research at the University Library of the Vienna University of Economics and Business (WU), 696 books which had belonged to Leopold Singer were identified. These were restituted to his heirs in 2015. They in turn donated the majority of the works to the library of the Technical Museum of Vienna (Technisches Museum Wien, TMW). In 2017, part of this book collection was incorporated into the TMW’s permanent exhibition on oil and gas. The stylised reconstruction of Singer’s library is presented there explicitly as the result of provenance research by WU Vienna.