From a book called _Legacies of Ewan MacColl: The Last Interview_ (MacColl in 1988):

"I only know one sea shanty that is based on a ballad... 'Lowlands'... All the rest, they're usually bawdy pieces or satiric pieces or complaining pieces, you know, like [singing] 'Liverpool I was born, bring 'em down / London is me 'one from 'one, bring 'em down...' That is very typical of the long drag shanties..."

So now it's become a yard halyard song!