The Anglo-Norman trouveres arranged these tales in graduated circles around their nucleus, the legend of the Holy Grail.

Next in importance to this sacred theme, and forming the first circle, were the stories of Galahad and Percival who achieved the Holy Grail, of Launcelot and Elaine who were favored with partial glimpses of it, and of Bors who accompanied Galahad and Percival in their journey to Sarras.

The second circle included the stories of Arthur and Guinevere, of Geraint and Enid, of Tristan and Isolde, of Pelleas and Ettarre, of Gareth and Lynette, of Gawain, and of Bedevere.

The third and last circle dealt with the epics of Merlin and Vivien, Uther and Igerne, Gorlois, and Vortigern.
To give a complete outline of the adventures which befell all these knights and ladies in the course of seventeen epics and romances,--of which many versions exist, and to which each new poet added some episode,--would require far more space than any one volume would afford.

A general outline will therefore be given of the two principal themes, the Quest of the Holy Grail and King Arthur and his Round Table, mentioning only the main features of the other epics as they impinge upon these two great centres.
Some of the greatest writers of the Arthurian cycle have been Gildas, Nennius, Geoffrey of Monmouth, Wace, Robert de Borron, Marie de France, Layamon, Chrestien de Troyes, Benoit de St.Maur, Gaucher, Manessier, Gerbert, Knot de Provence, Wolfram von Eschenbach, Gottfried von Strassburg, Hartmann von der Aue, Malory, Tennyson, Swinburne, Howard Pyle, Matthew Arnold, and Wagner.