Hans Ferdinand Mayer - The Oslo Report

The Oslo Report

Hans Ferdinand Mayer was the author of the Oslo Report, perhaps the most serious breach of German security in World War II. He signed it as "a German scientist, who is on your side", before sending it to the British Embassy in Oslo, Norway, in early November 1939. In his position at Siemens he had access to a wide range of information regarding the development and application of electronics in current and future weapons systems and radar.

The breadth (and uneven quality) of information in his Report led to initial scepticism amongst the British intelligence community about its veracity, but the technical detail of the information concerning electronics caught the attention of Dr. R.V. Jones, a brilliant young scientist who had recently been appointed to the Air Ministry. Jones, who was highly regarded by Churchill and eventually rose to the position of Assistant Director of Intelligence (Science), found the Oslo Report extremely useful in anticipating and countering the deployment of new German radar systems, and the radio beam systems used to guide German bombers to their targets.

The existence of the Oslo Report became more widely known through a talk given by Jones in 1947, although he did not become aware of its author's identity until late 1953, finally confirming it by meeting Mayer in 1955. He agreed to keep his identity secret, to avoid possible retribution against Mayer and his family.

Mayer did not tell his own family until 1977 that he had written the Oslo Report. His will was written so that his authorship of the Report would only be published after the death of himself and his wife. Jones respected Mayer's wishes, not revealing his identity until 1989.