Based on a footnote in Josceline Bagot's George Canning and His Friends, the British Museum commnentary identifies the subject of this print as "Captain Cunningham of the Coldstream." In her Curator's Note, Dorothy George then goes on to say that he "was a nephew of Mrs. Wortley wounded in Holland in 1799" and that in the Army List he appears as as "Captain and Lt.-Col. Francis Cunynghame."
There are several problems with this identification.
© Lewis Walpole Library, Yale University
First, among the various spellings of Cunningham in A List of the Officers of the Army and Marines published by the War Office in 1797, (p. 422) the only Francis listed is Major (not Captain) Francis Cuninghame of the "Thirty-fourth (or the Cumberland) Regt. of Foot—NOT the Coldstream Guards (p. 168). Second, the only Captain and Lieutenant Colonel Cunynghame is David (not Francis) and he was in the "Third Regiment of Foot Guards,"—again NOT the Coldstream Regiment of Foot Guards (p. 98). Third, all of these officers are foot soldiers, but the uniform of the subject is that of a "Light Horse" Guard.
But to my mind, the most significant problem with the identification is that it goes against the major convention of portrait caricature—that the title contain a clue to the subject's identity. A Dash Up St. James's Street does not describe the actions of the subject. He is not running or dashing anywhere. So the title would make much more sense if the name of the officer portrayed here were something similar to Dash or Dashwood, not Cunningham. And if we look through A List of the Officers of the Army and Marines with that in mind, we come across a Charles Armand Dashwood in the list of officers (p. 423 and p. 51). He was a Captain of the Royal Regiment of Horse Guards, and would therefore be associated with the Royal Palace at St James. He would likely have worn the uniform of a Light Horse Guard. And he was born in 1768 which would have made him 29 at the time of the portrait, consistent with the appearance of the young man in the print.
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