One theme which crops up from time to time in Deighton's works - in the Game, Set and Match novels with the Bernard Samson character, in particular the Winter prequel novel, detailing the post-war Berlin of his father; in XPD and Funeral in Berlin - is the role and influence of the networks set up by Reinhard Gehlen, which I've been reading up on recently online. It's a fascinating early part of the history of the Berlin spy networks and I've found some interesting snippets of information about it from my research. It's a fascinating story and you can see why Deighton would use it as source material for some of his stories.
The Gehlen Organization wasn't a total success, despite considerable funding by the US. Indeed, one author on the US and the Nazis, Richard Breitman, has written: