When romance "is in," and, after Geoffrey of Monmouth, romance _was_ in, every other kind of literature "is out"; is unfashionable and little regarded. The English rhyming chroniclers, and even religious writers such as the author of the "Cursor Mundi," felt constrained to make their works resemble fiction as nearly as possible; owing to the supremacy of French romances and English translations and adaptations of French romances, in the late twelfth, thirteenth, and fourteenth centuries. Many of these productions grouped themselves round the Table of King Arthur, "matter of Britain"; others dealt with "matter of Rome," that is all the ancient world; others with "matter of France"; others with legends or fancies, English or foreign. Their subject was often the chivalrous theory and practice of love, as a kind of religion, a fantastic semi-idealized devotion to the beloved, who, as a rule, was another man's wife. This breach of recognized religion and morality was often set down to fate, to the power that the Anglo-Saxons named _Wyrd._ The two greatest cycles of romantic love are found in the lives of Tristram and Iseult (the wife of King Mark of Cornwall, and aunt by marriage of Tristram), and of Lancelot and Guinevere, the wife of King Arthur. Tristram (whose name seems to be altered from the Welsh name Drysdan), has but little original connexion with the Court of Arthur, though he is a mythical hero of a very old Welsh "triad". He and Iseult love each other because they have by mischance drunk together of a love potion intended for Mark and his wife; their love is fatal and inevitable, and immortal. Lancelot, on the other hand, has been sent to bring the bride Guinevere to Arthur, and they fall in love before the lady has seen her lord. Every one knows their joys and sorrows, from Malory's "Morte d'Arthur," (1470)--a prose selection and compilation of "the French books," which excels them and supersedes them--and from the poems of Tennyson, Matthew Arnold, and Mr. Swinburne. The romances of love and tournament are pervaded and darkened by the influence of the Celtic Merlin, the enchanter and prophet whom men call Devil's son; he represents Destiny. A wide circle of romances, "Merlin" and the "Suite de Merlin," attributed to Robert de Borron, at the end of the twelfth century, are concerned with him. As if to counteract the fanaticism of love which, in the romances, becomes a non-moral counter-religion, the mysterious story of the Holy Grail came into literature, French, German, and English. The Grail is perhaps originally one of the many magical things of Celtic legend, a vessel as rich in food inexhaustible as the purse of Fortunatus in gold, but conceived by the romance writers to be a mystic dish or cup, used by our Lord before His passion, and still existing, but only to be seen by the pure of heart, such as Sir Percival, and Sir Galahad, the maiden son of Lancelot.