Thenceforth Arthur disappears from history.  What was his end no one knows.  The chronicle of the Abbey of Margan in South Wales, a chronicle of which the only known manuscript ends with the year 1232, and of which the portion dealing with the early years of John’s reign was not compiled in its present form till after 1221 at earliest, asserts that on Maunday Thursday (April 3, 1203), John, “after dinner, being drunk and possessed by the devil,” slew his nephew with his own hand and tied a great stone to the body, which he flung into the Seine; that a fisherman’s net brought it up again, and that, being recognized, it was buried secretly, “for fear of the tyrant,” in the Church of Notre Dame des Pres, near Rouen.  William the Breton, in his poem on Philip Augustus, completed about 1216, relates in detail, but without date, how John took Arthur out alone with him by night in a boat on the Seine, plunged a sword into his body, rowed along for three miles with the corpse, and then threw it overboard.  Neither of these writers gives any authority for his story.  The earliest authority of precisely ascertained date to which we can trace the assertion that Arthur was murdered was a document put forth by a personage whose word, on any subject whatever, is as worthless as the word of John himself—­King Philip Augustus of France.  In 1216—­about the time when his Breton historiographer’s poem was completed—­Philip affected to regard it as a notorious fact that John had, either in person or by another’s hand, murdered his nephew.  But Philip at the same time went on to assert that John had been summoned to trial before the supreme court of France, and by it condemned to forfeiture of all his dominions, on that same charge of murder; and this latter assertion is almost certainly false.  Seven months after the date assigned by the Margan annalist to Arthur’s death—­in October, 1203—­Philip owned himself ignorant whether the Duke of Brittany were alive or not.[34] Clearly, therefore, it was not as the avenger of Arthur’s murder that Philip took the field at the end of April.  On the other hand, Philip had never made the slightest attempt to obtain Arthur’s release; early in 1203, if not before, he was almost openly laying his plans in anticipation of Arthur’s permanent effacement from politics.

The interests of the French King were in fact no less concerned in Arthur’s imprisonment, and more concerned in his death, than were the interests of John himself.  John’s one remaining chance of holding Philip and the Bretons in check was to keep them in uncertainty whether Arthur were alive or dead, in order to prevent the Bretons from adopting any decided policy, and hamper the French King in his dealings with them and with the Angevin and Poitevin rebels by compelling him to base his alliance with them on conditions avowedly liable to be annulled at any moment by Arthur’s reappearance on the political scene.  If, therefore, Arthur—­as is most probable—­was now really dead, whether