Dorothy L. Sayers published "The Wimsey Papers" in
The Spectator
in 1939 and 1940, purporting to be between characters from the Wimsey novels. Aside from their interest to fans of Sayers, who would like to know more about her characters and about her views on the war, they're also interesting pieces of social history — these must be one of the last few pieces of writing where the word 'propaganda' is used in a neutral meaning, for example.