Only two contemporary writers even pretend to give a circumstantial account of Arthur’s death: the Annalist of Margam and William of Armorica. The former tells us that John, “post prandium, ebrius et dæmonio plenus” [did John, as well as Richard, make the demon-blood answerable for his sins?], slew Arthur with his own hand, and having tied a great stone to the body, flung it into the Seine; thence it was drawn up in a fisherman’s net, recognized, and buried secretly, “propter metum tyranni,” in Notre-Dame-des-Prés (Ann. Margam, a. 1204; Luard, Ann. Monast., vol. i. p. 27). William allows the murderer no such excuse, if excuse it be, but works up the story into a long and horrible romance, in which John deliberately and of set purpose takes Arthur out alone with him by night in a boat on the Seine, plunges a sword into his body, and then rows along for three miles before he flings the corpse overboard (Will. Armor. Philipp., l. vi.; Duchesne, Hist. Franc. Scriptt., vol. v. pp. 166, 167). Both these writers place the scene at Rouen. The Chron. Brioc. (Morice, Hist. Bret., preuves, vol. i. col. 39) transfers it to Cherbourg: “Apud Cæsaris-burgum duxit, et ibi proditorie et tyrannice eum in mare submersit.” Rigord says not a word of the matter. R. Coggeshall (Stevenson, p. 145) only speaks of it incidentally, saying that Philip “sæviebat ... permaxime pro nece Arthuri, quem in Sequanâ submersum fuisse audierat.” Rog. Wend. (Coxe, vol. iii. p. 170) says merely “subito evanuit.” Mat. Paris in Chron. Maj. (Luard, vol. ii. p. 480) copies this, and adds: “modo fere omnibus ignorato; utinam non ut fama refert.” In Hist. Angl. (Madden, vol. ii. p. 95) he gives three stories as currently reported: accidental drowning, death from grief, and the third, “ipsum manibus vel præcepto regis Johannis fuisse peremptum”—this last being the assertion of the French, “quibus propter hostilitatem plena fides non est adhibenda.” But his own words in the Chron. Maj. shew that he could not wholly reject the unavoidable conclusion of John’s guilt.
The date of Arthur’s disappearance or death is given only by the Margam annalist. He places it on Maunday Thursday; but unluckily he has damaged his own authority on chronological matters by putting the whole affair a year too late, viz. in 1204 instead of 1203. Will. Armor., on the other hand, tells us that for three days before the murder John was at Moulineaux, near Rouen. These two chronological indications do not exactly agree, for in 1203 Maunday Thursday was April 3, and the Itin. K. John, a. 4 (Hardy, Intr. Pat. Rolls), shews that the king was at Moulineaux on Wednesday, April 2, but on the two preceding days he was at Rouen. It is however plain from the after-history that the deed must have been done shortly before Easter.