It was collected in Småland or Blekinge by Gunnar Olof Hyltén-Cavallius and George Stephens and published in Svenska folksagor och äfventyr (1:1-2, 1844-49).
It has been filmed on several occasions and forms the basis of Erik Bergman's opera Det sjungande trädet.
The themes of marriage to the monstrous or mysterious husband, of curiosity inspired by the mother, and even the drops of spilled tallow are very similar to the Hellenistic romance of Cupid and Psyche.
The princess goes to Prince Hat's lair and spends the days all alone in his subterranean abode, but when night falls, he returns and he is always tender and caring.
At the third visit, her stepmother gives her a wax candle that she is to hold over her sleeping husband to see his face.
To her happy surprise, she sees a beautiful young man, but a drop of wax falls onto his chest.
in this tale type, the heroine is a human maiden who marries a prince that is cursed to become an animal of some sort.
[8] The motif of the separation of the heroine from her children is located by scholarship across Celtic and Germanic speaking areas.
[9][10][11] According to Hans-Jörg Uther, the main feature of tale type ATU 425A is "bribing the false bride for three nights with the husband".
[12] In fact, when he developed his revision of Aarne-Thompson's system, Uther remarked that an "essential" trait of the tale type ATU 425A was the "wife's quest and gifts" and "nights bought".
[13] As part of the journey to her husband, the heroine may be helped by three old crones - a motif that appears in European variants.
She then decides to fatten it until it grows large, kills it and uses its hide as part of a riddle for anyone (tale type AaTh 621, "The Louseskin").
One day, the princess sends her father a letter about her situation, and the king tells her to take a flint and light a candle at night.
[15][16] In a Finnish-Swedish tale collected by G. A. Åberg from Degerby with the title Prins Lopandiorm ("Prince Running Snake"), a princess finds a louse in her father's hair.
Continuing on her journey, she overhears two ravens talking to each other about Prince Lopandiorm bring held prisoner by a witch in a castle somewhere.