When he was wounded to death he said, "I have long been at war against my conscience." At sight of his dead body on the field of battle young John of Montfort, his conqueror, was touched, and cried out, "Alas my cousin, by your obstinacy you have been the cause of great evils in Brittany: may God forgive you! It grieves me much that you are come to so sad an end." After this outburst of generous compassion came the joy of victory, which Montfort owed above all to his English allies and to John Chandos their leader, to whom, "My Lord John," said he, "this great fortune path come to me through your great sense and prowess: wherefore, I pray you, drink out of my cup." "Sir," answered Chandos, "let us go hence, and render you your thanks to God for this happy fortune you have gotten, for, without the death of yonder warrior, you could not have come into the inheritance of Brittany." From that day forth John of Monfort remained in point of fact Duke of Brittany, and Joan of Penthievre, the Cripple, the proud princess who had so obstinately defended her rights against him, survived for full twenty years the death of her husband and the loss of her duchy.
Whilst the two Joans were exhibiting in Brittany, for the preservation or the recovery of their little dominion, so much energy and persistency, another Joan, no princess, but not the less a heroine, was, in no other interest than the satisfaction of her love and her vengeance, making war, all by herself, on the same territory.

Several Norman and Breton lords, and amongst others Oliver de Clisson and Godfrey d'Harcourt, were suspected, nominally attached as they were to the King of France, of having made secret overtures to the King of England.

Philip of Valois had them arrested at a tournament, and had them beheaded without any form of trial, in the middle of the market-place at Paris, to the number of fourteen.

The head of Clisson was sent to Nantes and exposed on one of the gates of the city.

At the news thereof, his widow, Joan of Belleville, attended by several men of family, her neighbors and friends, set out for a castle occupied by the troops of Philip's candidate, Charles of Blois.