Correspondence with Captain S.W. Roskill on the latter's historical research, especially on the Belligerent Rights at Sea Treaty.

Correspondence with Norman Hillmer about the latter's research on Anglo-Canadian relations between the Wars.

Papers on Canada and the history of the Commonwealth in general, by Hillmer and others.

Correspondence with various researchers on different historical matters.

Letters by Batterbee, which were published in The Times, with resulting correspondence and other press cuttings.