An anonymous fifteenth-century Meisterlied based on the tale first attested in Robert Biket’s Lai du cor, “Dis ist Frauw Tristerat Horn von Saphoien” (‘This Is Frau Tristerat of Savoy’s Horn’).
A young lady bearing a magic drinking horn arrives at King Arthur’s court one day. The horn has been sent by Lady Tristerat to test the fidelity of the ladies at Arthur’s court. That man who is able to drink from the horn without spilling a drop has a faithful wife. First, Arthur and then the kings of mighty lands attempt to empty the horn without mishap. Only the king of Spain succeeds, and his wife, the most beautiful woman present, turns out to be the only faithful woman.
See also
Chastity Test | The Legend of King Arthur