Hermann Voss studied art history, music history and history in Heidelberg. Following his doctorate in 1906, he lived in Italy and in 1908 began an internship at the Königlich Preußische Kunstsammlungen zu Berlin with Wilhelm Bode. In 1912 he became head of the Graphic Arts Collection at the Museum of Fine Arts in Leipzig, in 1922 curator of the Picture Gallery of the Staatliche Museen in Berlin and from 1935 director of the Städtische Kunstsammlung at the Landesmuseum Wiesbaden. Voss took the opportunity during the seizure of "degenerate art" in 1937 to improve the situation of the Wiesbaden museum through barter or compensation. At the latest from 1937 he approached the National Socialists, gave talks to SA leaders and worked at the start of the war as an art expert in occupied France and as an assessor for the Wiesbaden police, but was not himself a member of the NSDAP. His appointment as successor in December 1942 to the deceased Hans Posse was surprising and must have been as a result of a decision by Posse himself. Despite the defeat of the German Wehrmacht in Stalingrad in February 1943, Voss was entrusted with continuing the "Sonderauftrag Linz". Unlike his predecessor Posse, Voss was only in charge of the painting, graphic art and sculpture collections, while Fritz Dworschak, Friedrich Wolffhardt and Leopold Ruprecht (all from Vienna) continued to be responsible for the numismatic collection, the arms collection, and the library. Other agendas, including the important coordination of salvaging and depots remained under the aegis of Gottfried Reimer, the special representative for "Sonderauftrag Linz", a position he had held temporarily after Posse's death. Voss's activities were thus confined to coordinating further acquisitions. He had recourse to a large network of art dealers and agents both within the German Reich and in the occupied territories. Unlike his predecessor Posse, Voss only made three trips, and he did not personally inspect the majority of the acquired art works. He nevertheless made considerable acquisitions: he claims to have purchased almost nine hundred paintings, several hundred prints and a few sculptures and applied art objects between April 1943, when he took office, and March 1944. Because of the enormous outlays, there were fierce arguments with Reich Minister and head of the Reich Chancellery Hans Heinrich Lammers, who was responsible for finance. In summer 1944 – the Allies had already landed in Normandy – Lammers informed Reichsleiter Martin Bormann that the monthly expenditure for the "Sonderauftrag Linz" had reached 6 million Reichsmarks. Despite this, Voss continued to provoke the Reich Chancellery by demanding funds for his special foreign exchange accounts. Lammers protested, but Hitler showed no willingness to limit the funds available. The exorbitant increase in costs, compared with Posse, can be explained by the fact that Voss concentrated on acquisitions from the art market, while in the initial phase of the "Sonderauftrag Linz" most of the objects were taken directly from expropriated collections, in particular from the Zentraldepot für beschlagnahmte Sammlungen (Central Depot for Seized Collections) in Vienna. Voss's claim when interrogated after the war that as special representative he was not involved in the art looting by the National Socialists is untrue. He acquired objects directly from seized collections, such as that of Adolphe Schloss in France. He also took many objects directly from Vugesta. Furthermore, many of the objects acquired from dealers or agents were from forced sales or expropriations. After the defeat of the German Reich, Voss nevertheless claimed to have been politically uninvolved and intent as special representative merely on rescuing art treasures. His strategy proved successful. Although he was interrogated by the Art Looting Investigation Unit in summer 1945 in Altaussee, he was not charged by the allied forces nor was he later called to account by the German authorities during denazification proceedings. In 1947 he published a book entitled Deutsche Selbstkritik with the intention, as his biographer Kathrin Iselt described it, "to make known his attitude as an anti-Fascist and cosmopolitan, without having to talk about his own role and position in the Nazi system." Until his death, Voss, who lived in Munich after 1945, published numerous essays on art history, particularly research into sixteenth- and seventeenth-century Italian painting. He was recognized as an art historian and assessor and until 1968 was a member of the Purchasing Commission of the Bayerische Staatsgemäldesammlung (Bavarian State Painting Collection). He had a private art collection, most of which was secured by the German police in Dresden in 1946, after which it was moved several times, all trace of it being lost by the end of the 1940s. Even today, neither the origins nor the whereabouts of the paintings and prints are known.