I am intrigued - like many other readers, I presume - by the titles PK and his editors chose. They often have a slightly mystical or literary flavour, and while I think many of them are very well chosen, I can't quite comprehend others. Care to enlighten me, readers?
"March Violets" was, according to PK, a contemporary term for those who jumped on the Nazi bandwagon with only minimal hesitation, once it became clear that there was no viable political opposition - i.e. in March 1933. While mysterious until you start reading the book, I think it is works well - it intrigues potential buyers and then satisfies their curiosity, and is apt.
"The Pale Criminal" evidently refers to the physical appearance of Reinhard Heydrich who enters the BG canon at this point and is a lead figure in the book. Interestingly PK says he originally wanted the title to be "The Man With A Heart of Iron" but couldn't because there was a prior publication with this title.
"A German Requiem" (too little connection is made, IMHO, to the otherworldly beautiful Brahms composition of this name) is a non-too-subtle riff on Carol Reed and Graham Greene's "The Third Man" (with Emil Becker standing in for Orson Welles) - but whose requiem is it exactly? BTW, although written 15 years before the next instalment in the BG canon, this title would have been equally suitable as an epitaph for Kirsten whose slow death (and its causation) is an important plot anchor in the Munich-set sequel, I think.
Nonetheless, "The One From The Other" is a brilliantly eccentric title, and makes sense both in the way Niebuhr uses it in his often-quoted prayer, and in the way the shadowy world of post-war secret services endeavours to utilise the misbegotten research conducted inside the Third Reich, and snooker each other, while clandestine zionist avengers pursue SS criminals with deadly force, with GB as usual playing piggy-in-the-middle.
"A Quiet Flame" I haven't read yet, so will hold commenting on.
"If The Dead Rise Not", and "Field Grey", likewise.
I'm currently a quarter through "Prague Fatale", which presumably refers to Heydrich's demise (interestingly it was almost certainly a pulmonary embolus from deep venous thrombosis caused by complete bed rest after the badly bungled assassination attempt that killed him - he enjoyed very competent surgical management even before the SS-doctors arrived on the scene). Presumably a riff on "femme fatale" - but who is the femme: the city of Prague?
"A Man Without Breath" is a slightly mysterious title - perhaps referring to the first Polish officer found at Katyn, or metaphorically to the prototype Junker of which there are several: The craven von Kluge, as well as von Tresckow, von Gerstorff, and von Schlabrendorff, all of whom seem prisoners of their arch-conservative and privileged upbringing; their stiff politesse prevents them from doing the necessary without scruples insofar as killing Hitler is concerned. Although one might argue that it could well refer to the dictator himself, who enjoyed breathtakingly good luck to survive so many assassination attempts ...