The song 'Old Billy Riley' most likely originates from either the sugar trade or 'cotton-stowers' who moved cotton from ship holds and used jackscrews to force the cotton bales in tightly. Both of these origins were heavily involved in slavery and it most likely originated from black people on these ships.

'Billy Riley' is most likely not a person, but the personification of a sail. The song is a halyard shanty, and due to the fast tempo would be extremely tiring work. The song mentions that 'Billy Riley was a dancing master' which could indicate the sail moved a lot, which reinforces the idea of fast tiring work. The song mentions 'Billy Riley's 'nice young daughter' which is probably a smaller 'more behaved' sail and it also mentions that the sailors 'can't get at her' which indicates that 'she' may have been a moonsail.

The song also mentions 'Billy Riley' being a 'master of a drogher'. A 'drogher' is either a flimsy disposable ship or a small sailing ship which were common in the west indies sugar trade.