Through his work at Springer Verlag, Rosbaud knew much of the scientific community in Germany, and as a presumed Nazi, he had sources of vital intelligence relating to weaponry. In 1935 he began to work for the Naturwissenschaften review. In 1938 he had his Jewish wife Hilde and their only daughter Angela sent to the UK to keep them safe from Nazi harassment. Rosbaud was also invited to stay in the UK, but he decided to keep working in Germany to undermine the Nazi regime. In addition to his own, Rosbaud helped a number of other families flee the Nazis, including that of the well known Jewish physicist Lise Meitner. He was assisted in his work saving Jews by the fact that he was run as a British agent by Frank Foley, the MI6 station chief in Berlin. Eric Welsh and presumably also Foley were Rosbaud's contacts in SIS/MI6. , was one of Rosbaud's contacts in Oslo. Goldschmidt was of Jewish and bohemian background and in 1942 narrowly escaped deportation to Auschwitz. Before the outbreak of war, Rosbaud hurried into print Otto Hahn's work on nuclear fission in the German physics magazine Naturwissenschaften in January 1939. Paul Rosbaud realized the vast destructive potential of what Hahn, Strassmann, and Meitner had discovered, and he was acutely conscious that the fundamental research had been done in Germany. He wanted the rest of the world to know of the significance of the work at least as soon as the Nazi planners did. By rushing into print with Hahn's manuscript he was able to alert the world community of physicists. Rosbaud was in Oslo August 26 to September 16, 1939, a few days before Frank Foley abandoned Berlin and transferred to Oslo. There he visited Victor Goldschmidt a geologist that also studied the properties of uranium and "super-uranium". In Oslo Rosbaud also met Odd Hassel, an old acquaintance. Goldschmidt and Rosbaud were friends and when persecution of Jews in Germany intensified in 1935 Rosbaud helped Goldschmidt abandon Göttingen and return to Oslo. Late autumn 1939 Rosbaud was again in Oslo and urged Odd Hassel to warn Norwegian authorities about a likely German invasion of Norway. During the German occupation of Norway, Rosbaud visited Oslo in German uniform and met professor Tom Barth, who had connections with the resistance movement. Among the reports he supplied to the British was that Germany produced rockets and that the German project for a nuclear bomb was not successful. Rosbaud has also been connected to the "Oslo report", a detailed list of new German weapons systems, but this seems to be the work of Hans Ferdinand Mayer, technical director at Siemens. Many of his reports were smuggled out of Germany by couriers working for the Norwegian intelligence organisationXU. Norwegians who were studying at technical schools in Germany, such as Sverre Bergh, linked up with Rosbaud and transported the intelligence to occupied Norway, and from there it was sent to neutral Sweden. One daring route involved a flight from Berlin to Oslo, with airport mechanics at each end helping to hide microfilms on the plane. Rosbaud supplied Moe Berg and Horace Calvert with a list of scientists in the Russian sector of Berlin when scientists were sought to join the victors after the war.
Pergamon founder and editor
After the war, Rosbaud took up residence in England. He worked for Butterworth-Springer, a company set up in response to a Scientific Advisory Board that included Alfred Egerton, Charles Galton Darwin, Edward Salisbury, and Alexander Fleming. When the Butterworth Company decided to pull out of the English/German liaison, Robert Maxwell acquired 75% while 25% rested with Rosbaud. The company name was changed to Pergamon Press; the partners, with their considerable language skills, cooperated in establishing new academic journals until 1956. After a disagreement, Rosbaud left. Maxwell said Rosbaud "was an outstanding editor of the European type from whom I learned some of the trade in the early days". In 1961 the American Institute of Physics presented Paul Rosbaud with the first John Torrence Tate Medal, an "award for service to the profession of physics rather than research accomplishment".
