'They were found mostly on British and other European ships'<<<<<

I think Gibb would have something to say about that. I think a more accurate statement would be they were published mostly in British anthologies. Evidence would suggest that at least half the references are of American origin and that's certainly where they originated, and indeed onshore. the first use of the word 'chantyman' as a worksong leader was for a stevedore in the Gulf ports.

Wiki seriously needs an update!