Thank you, very informative.
I wonder if you looked up the plate referenced prior to posting?
The description of the plate in the index reads "Napoleon in campaign uniform"
Uniform depicted: (forgive description, as not a specialist) habit (long) dark green; colour and (plain) cuffs deep red (no cuff slashes visible); turnbacks green piped deep red, ditto lapels.
The following catalogue entry provides details of the provenance and source of the work
Arnold, Friedrich (1831-1862) after Dähling, Heinrich (1773-1850)
Likely year = 1806
http://digital.library.mcgill.ca/napoleon/search/printsdetail.php?ID=1349&doctype=Prints&sitelanguage=english
Best wishes
A