The story is classified in the international Aarne-Thompson-Uther Index as tale type ATU 400, "The Man on a Quest for the Lost Wife", in a form of the narrative that, according to scholars, appears in Northern Europe, namely, in Scandinavia and the Baltic Sea.
When it is the youngest's turn, near "the hour of the matins", he sees three doves coming to the meadows, take off their plumages and become human maidens.
The youth agrees to their pleading, but first he wants some explanations: one of the girls says they are a princess and two court attendants that live in a palace east of the sun and north of the earth.
One day, he finds two giants fighting over their father's inheritance: a pair of magical boots that allow its wearer to take a hundred miles with every step.
He goes after her on a long quest, often helped by the elements (Sun, Moon and Wind) or by the rulers of animals of the land, sea and air (often in the shape of old men and old women).
[15] Finnish folklorist Oskar Hackman summarized some Finnish-Swedish variants in his publication Finlands svenska folkdiktning under the banner Konungariket Midnattssol ("The Kingdom of the Midnight Sun").
The third son ties his feet to a tree to avoid falling asleep and to be jerked awake by the summer storm.
Reaching the island's shores, the youth puts on the invisibility hat, creeps into the castle and places her ring on a water jug.
They marry, but a local emperor covets the girl and orders the man to fulfill three tasks: to fell down a whole forest, then put it back, and steal the keys from an enchanted castle.
[22][23] August Bondeson collected a Swedish tale titled Herregården, som var belägen öst om solen och väst om vinden i det förlovade landet ("The Castle East of the Sun and West of the Wind in the Promised Land "):[24] a miller finds out that the grains at his mill are disappearing, since the mill is locked at night, and decides to investigate.
She agrees, gains her clothes back, tells the man to seek her home: the mansion located east of the Sun, West of the wind in the promised land, and flies away.
In this tale, a peasant has a wheat-field that something has been trampling every Saturday night, so he orders his three sons to keep guard on the fields to discover the culprits.
On the third night, John of the Ashes manages to stay awake and discovers three doves come, shake off their feathers and become maidens.
[26] According to Ørnulf Hodne [no]'s The Types of the Norwegian Folktale, the tale was originally collected in Vestfold with the title Sønna for sø og nora for nor, inde ved det store Guldberget.
In this tale, translated into German as Die Burg östlich vom Mond und südlich von der Sonne ("The City east of the Moon and South of the Sun"), a royal couple celebrates the long awaited birth of their son.
The girl begs to have her swan cloak back, for she is the daughter of the King of the Clouds, who lives in a castle east of the Moon and South of the Sun.
The next morning, the princes notices his wife is missing, and tries to take his own life, but his mentor dissuades him, and suggests they begin a journey to the Cloud King's realm.
[30][31] German lexicographer Jens Andreas Friis collected a Sámi folktale titled Baeive-Kongens Datter or Die Tochter des Beivekönigs ("The Daughter of the Beive-King").
In this tale, a farmer has three sons, the youngest called Gudnavirus (Askeladden, Ashlad, Male Cinderella) for he likes to play in the ashes of the fireplace.
Still intent on fulfilling the king's last task, Gudnavirus goes on a quest to the Kingdom of Darkness, first by following the sunlight until it fades, then the moonlight until is ceases, and finally the light of the stars.
[32][33] In a Sámi tale collected by Norwegian scholar Just Qvigstad from a source in Lyngen and titled Det forgylte slott (English: "The golden castle"), an old woman has three sons, the youngest named Askeladden ("Gudnabađǫš", in the original).
Later, the girl comes on a ship, but the local king forbids Askeladden to depart, only allowing his voyage if the boy fulfills some tasks beforehand: first, to gather all stones on the fields; next, to stock them in piles; thirdly, to raze every tree in his land, then to plant them again; lastly, to steal back a silver box from the giants.
With his bride's help Askeladden fulfills the first tasks, one after the other, but, on the last one, the girl says she cannot wait any longer, gives him a golden ring engraved with her name, and departs on her ship.
When it is the youngest's turn, he remains awake by walking about and, when midnight strikes, the three swans come, take off their feathers and become human maidens.
He, however, covers her with a coat and let her tell her story: the girls are enchanted princesses who live in a kingdom of rainbow fountains which have dried, and they take flight to bathe in distant regions.
The next day, the king congratulates his youngest son for protecting his garden, but the prince wishes to begin a journey to find the swan princess.
On the road, he finds three giants quarreling about three magical objects: a pair of seven-league boots, a cloak of invisibility, and a feathered hat that produces a loud noise like the shooting of cannons.
[41] According to the Finnish Folktale Catalogue, established by scholar Pirkko-Liisa Rausmaa, type 400 is known in Finland with the title Kadonnutta vaimoa etsimässä ("Looking for a lost wife"): the hero finds a maiden of supernatural origin (who may be a swan maiden), loses her for some reason (after she arrives on her ship, or he spends too much time on a certain place); with the help of animals, he crosses three seas to find her at her enchanted castle.
However, a local king sees the maiden and wants to have her for himself, so he sets three tasks for the poor bridegroom: to fell an entire forest, then raise it back, and steal a key from a certain palace.
The man fulfills the first two tasks, and goes to steal the key from the magic castle, but, on his way back, falls off the horse, due to the pursuing animals.