2The creation of MI9 in December 1939, the rationale for the new military intelligence branch and the context of the history of military mapping on silk is outlined in this history. The map production program is described, together with its progress and the challenges faced. The various groups of maps are identified and described, together with the source maps on which they were based. The ingenious methods of smuggling the maps into the camps, with other escape aids, in apparently innocuous leisure items are described. The maps were then copied and reproduced to support the escapes. Coded correspondence with the camps is discussed, and a successful deciphering of some of that correspondence is provided.