I sing the same version that's in DT, give or take a note or two. I learned it from Walt Robertson back about 1953 or so. I subsequently found it in "The Burl Ives Songbook" (paperback).

Perhaps one of the first examples of what, during WW II was known as a "Q ship" (never did find out what the "Q" stands for).

Barbary pirates were wreaking all kinds of havoc on the shipping of all countries. They would block merchant ships, then if they offered no resistance, loot them, then let them go on their way. Sort of an early protection racket. If the merchant ship resisted, the usual battle took place in which the merchant ship usually lost.

Fed up, the English navy sent out two ships fixed up to look like merchant ships, but were actually men o'war. They were "trolling" for pirates. If approached by a pirate, they would seem to cooperate, then when they sailed in alongside, sucker-punch them with a broadside.

During the Second World War, before the United States got into it, they were shipping stuff to England on the "Lend-Lease" program. German U-boats would attack any merchant ships heading for England, but would avoid destroyers or sub-chasers. When the U-boat came in close, assuming it was easy pickings, the "merchant ship's"—Q ship's—guns and/or depth charge launchers would suddenly go into action and blow the U-boat out of the water.

Don Firth