Gloucestershire is not known for sea shanties, although ships did and still do sail up the canal to Gloucester. The heyday of shanties was the 19th century when the singing of the shantyman would spur the sailors on, This was a factor in the competitive commercial nature of the shipping lines. I suspect it was widely known on the sailing ships but less so inland. It has been found throughout the English-speaking world.
Notes by Gwilym Davies 13 April 2016