All I can find out is that he is from Peterborough (near Cambridge in eastern England). he also wrote a book on Roman Roads, published 1979.
From
http://www.eastmidlandandeastanglia...deration.htm"16.5.51
ST. PETERSBURG AND THE ANTARCTIC.
We are pleased to note that a Peterborough member (R.A. Bagshawe) in conjunction with Mr John Goldup, has written a short, but authoritative, work on the "Postal History of Antarctica " from 1904-49. We have read this with considerable interest and feel that it is a worthy companion to Richard Bagshawe's previous work on the "Postal History of the Falkland Islands Dependencies". Those two works give a complete picture of the whole of the Antarctic region.
This latest work contains nearly 50 line blocks of cancellations, together with 8 photo-plates; in these days, this is a very lavish proportion of a work to be given up to illustrations.
Reprints may be obtained from, The Scott Polar Research Institute, Cambridge, at the small price of three shillings and ninepence, post free."
Further on, the editor apologises for calling him Richard A instead of Richard W.