Number 2145 in the Roud Folk Song Index. The majority of examples found in tradition are from England and Australia. Although Irish variants exist (Elizabeth Cronin had a set, beginning In the neat little town of Dunmanway), they seem mostly to be localised to Tralee; the famous example recorded by the Dubliners, since which the song has generally been supposed to be typically Irish, was learned by them from Ewan MacColl, who got it from Harry Cox. I think we discussed the song's possible movements in another thread not very long ago; it seems possible that a version localised to Belfast (and with "colleens" added for flavour) came back to Norfolk (there was a good bit of communication via the fishing trade when that was still going); though it appears that most of Harry's contemporaries in the area still sang the earlier "London" version.