"Young Beichan" is Child Ballad #53, collected in several variants, in which the hero's name, the heroine's, and the location where they meet vary a lot.
The plot, however, does not. The hero is thrown into a dungeon in a far country. His captor's daughter frees him, and he pledges to marry her. On returning home, however, he is forced to marry. She arrives in time to stop the wedding.
Full text, with all of Francis Child's variants, here.
Tropes included (in at least one variant):
- Blue Blood: Some variants note his high birth before recounting his imprisonment.
- Cold-Blooded Torture: The hero suffers this in prison.
- Cool Boat: The heroine uses a magical boat to reach the hero in time to stop his wedding.
- Cool Horse: The heroine gives one to the hero when he escapes.
- Distressed Dude: The hero is imprisoned and must be saved by the heroine.
- Fairest of Them All: When the heroine arrives, the porter declares her the most beautiful woman he ever saw. The bride's mother is miffed: If he did not except the bride, he might have excepted her.
- Mad Scientist's Beautiful Daughter: Despite Doing In the Wizard, still recognizable.
- Old Retainer: The family household sprite Belly Blin warns Isobel that her lover is about to marry another woman.
- Rule of Seven: The hero must return before seven years are up to marry the heroine.
- Swarm of Rats: The hero's hair is gnawed on by rats in prison:O whan she saw him, Young Bekie,
Her heart was wondrous sair!
For the mice but an the bold rottons
Had eaten his yallow hair.
- You Have Waited Long Enough: Directed at the man, for once.''Tak hame, tak hame your daughter dear,A blessing gae her wi,For I maun marry my Burd Isbel,That's come oer the sea to me.''
There is a wedding in yonder hall,
- In some variants, on arrival, the heroine finds that the wedding festivities have gone on for thirty days without the hero having consummated the union.
Has lasted these thirty days and three;
Young Beichan will not bed with his bride,
For love of one that's yond the sea.
- In some non-English variants, the hero has been magically forced to forget her.