The Lute Player — or The Tsaritsa Harpist — is a Russian fairy tale. Andrew Lang included it in The Violet Fairy Book (1901).
It is Aarne-Thompson type 888 The Faithful Wife.
The instrument actually described in the fairy tale is a gusli.
Synopsis
A king lived happily with his queen, but after a time, wanted to fight and so win glory. He set out against a wicked king, but lost and was captured. He sent a message to his queen to ransom him.
His queen thought that if she went herself, the wicked king would take her as one of his wives, and she did not know whether she could trust her ministers. She cut her hair, disguised herself as a boy, and set out with a gusli. She reached the court of the wicked king and charmed him with her music. He promised her whatever she wished, and she said she wanted a companion on the way, so she asked for one of his prisoners. He let her choose, and she picked the king.
They went back to their country without his discovering who she was. She left him before he reached his court. He was angry that his wife had not ransomed him, and even more angry that she had vanished and just returned, assuming she had been unfaithful. She disguised herself as the musician again, and her husband promised her whatever reward she wished. She told him she wanted him, and revealed she was the queen.