This is a variant of Willie o’ Winsbury, and one which departs from the usual storyline further than most. In this one the daughter isn’t pregnant and the father objects to “young John” on the general principle of protecting his daughter from excessive male attention. (There’s also the unusual detail of the boyfriend being called John and coming from the Isle of Man.) When they meet, of course, the King is so impressed by young John’s good looks that he drops his objections.
Both the tune and the phrasing are from a recording made by Robert Cinnamond (1884-1968), who had a large repertoire of songs learned from his father and grandmother. His delivery of this song – particularly the heavily dotted 4/4 rhythm and the emphatic swoops on unstressed syllables – was too distinctive not to imitate; I expect it’ll seep into the way I sing other songs.