Frank Purslow wrote in Marrow Bones:

"At daybreak on 21 June 1789, HM packet Princess Royal, nine days out from Falmouth on her way to New York (other accounts say Halifax) carrying mail, was accosted and pursued by a brig which was later identified as the French privateer Aventurier. At 7 pm the Aventurier hoisted English colours and fired a shot, which the Princess Royal returned. After a further shot, the brig continued the pursuit. It was not until 3.30 am on 22 June that the Aventurier resumed its attack, this time with a broadside and musket fire. The Princess Royal was outmanned, with a crew of thirty-two men and boys with seventeen passengers as opposed to the Aventurier's 85 men and boys; and out-gunned too, with six cannons against the brig's sixteen. Nevertheless, the English ship gave a good account of herself, holding the privateer off for two hours; at the end of which time the Aventurier moved away, sustaining further damage to her stern. The French ship was obliged to return to Bordeaux for refitting, while the Princess Royal resumed her course, eventually arriving home on 31 October.

If, as seems likely, this is the event that gave rise to our song, then it is a mystery why the broadside writer has toned down the story instead of embellishing it. Perhaps the full details were not immediately available; it is otherwise hard to see why a dramatic engagement should have become merely an account of a successful escape."