Tristan and Isolt's conflict of Любовь and loyalty is one of the classic tales of Western literature; in the Arthurian tradition, their tragic tragectory rivals and complements that of Lancelot and Guinevere. The basic story is one of mis-directed love: Tristan, the heroic nephew of King Mark of Cornwall, is sent to Ireland to escort the Irish king's daughter, the beautiful Isolt, to Cornwall to become his uncle's bride. In most versions, it is during the return voyage that Tristan and Isolt accidentally consume a Любовь potion (meant to ensure Isolt's happiness with Mark) together, and fall in love. Because Isolt's engagement to Mark cannot be broken, she marries the king despite her Любовь for Tristan, and the two Влюбленные spend the rest of their lives attempting to satisfy their desire for each other without revealing that desire to Mark and the Cornish court. Virtually all versions of the legend revolve around conflicting themes of romantic Любовь and political loyalty, though no two tellings treat these themes identically.

In spite of this preference for action over love, Tristan and Isolde hold a place in the Morte d’Arthur comparable to that of the other great Любовь story, that of Lancelot and Guinevere. Lancelot and Tristan are called the two greatest knights and greatest Влюбленные by Merlin, and the fairness of the two ladies is often compared. The basic outline of their tales is similar in that both knights are caught in a dangerous треугольник of emotion that pits their Любовь for their ladies against their loyalty to their king. The stories of the pairs are not, however, merely variations on a theme; there are notable contrasts between the two tales, not the least of which is the disparity between the two kings involved-- the generally noble and good Arthur has little in common with the malicious Mark.