Iains
The full history of 'The Wild Rover' is well documented and well-known and appears in several threads here. It appears to have started life indeed as a 17th century temperance song on a broadside probably written in London which is where all the presses were. It had many more verses but over the next 3 centuries was rewritten by broadside writers and reduced down eventually to the 5 verse 19th century broadside which gave rise to all of the oral versions.

Incidentally there is also a strong probability that The Green Bed evolved from the same original piece but by the 19th century they had no text in common and therefore are fully independent songs.