"Faithful John" is a German fairy tale collected by the Brothers Grimm, tale number 6.
In some variants, a king on his deathbed orders his servant, Trusty John, not to let his son see a certain room, which holds a portrait of a princess. - In all variants, when the new king comes to power, he forces his way into the room. Instantly, he falls in love with the princess. In Joseph Jacobs's version, her country had been at war with his, and the portrait stems from betrothal negotiations that had fallen through; but in all versions, the king does not know how to win her. Trusty John tells him to prepare a ship with all manner of rich treasure, and then either sails with it himself, or has the king sail with him, to her country. The princess is lured aboard by the goods, and the ship sets sail, carrying her off...
