There were several Trafalgar veterans who claimed to have shot the Frenchman who killed Admiral Nelson, but the most well known is John Pollard who was serving as Signal Midshipman on HMS Victory at the battle of Trafalgar.
Sir William Beatty in his Authenic Narrative of the Death of Lord Nelson wrote
'There were only two Frenchmen left alive in the mizzen-top of the Redoutable at the time of his Lordship's being wounded and by the hands of these he fell… At length one of them was killed by a musket ball; and on the others then attempting to make his escape from the top down the rigging, Mr Pollard (Midshipman) fired his musket at him and shot him in the back when he fell dead from the shrouds on the Redoutable's poop'.
Robert Southey in his Life of Nelson (pub 1813) credited both John Pollard and Midshipman Francis Edward Collingwood as being the 'avenger of Nelson'. However in a letter to The Times 13 May 1863, John Pollard wrote
'It is true my old shipmate Collingwood who has now been dead some years came up on the poop for a short time. I had discovered the men crouching in the top of the Redoutable and pointed them out to him, when he took up his musket and fired once; he then left the poop, I conclude, to return to his station on the quarter deck… I remained firing till there was not a man to be seen in the top; the last one I saw coming down the mizzen rigging and he fell from my fire also… I was ushered into the ward room where Sir Thomas Hardy and other officers were assembled and complimented by them as the person who avenged Lord Nelson's death.'