I've always been led to believe that 'Benjamin Bowmaneer' concerned the Napoleonic Wars.
'The proud tailor rode' etc...(tailors being 'figures of fun' in those days, presumably for sewing while real men did real work - but that's a whole different argument)...
The reference 'he spied a flea on his knee' I've been told
is a p**s-taking reference to Bonepart's small stature.
Anyone out there to correct or confirm?