Chronology
- 30 April 1341 – John III dies without heirs. Joanna and Charles of Blois became dukes of Brittany. John of Montfort refuses to accept and calls for the help of king Edward III of England.
- 1343 – John of Montfort is taken prisoner, but is released shortly afterwards. Charles tries to take advantage and attacks Hennebont, but the city is defended with success by Joanna of Flanders, wife of Montfort. An English army relieves the siege and forces the Blois to a truce, broken shortly afterwards.
- 1344 - Charles takes Quimper with the help of a French army, courtesy of king Philip VI of France, and slaughters 2000 civilians
- 1345 – John of Montfort fails to recover Quimper and dies. His ambitions over Brittany are inherited by is son John V. His mother, Joanna of Flanders, becomes the political and military commander of the Montfort faction.
- Between 1346 and 1364, several minor battles are won and lost by both parts, several truces are signed and broken
- 27 March 1351 - Combat of the Thirty
- 29 September 1364 – Battle of Auray. Bertrand du Guesclin and Charles of Blois are heavily defeated by John V and the English warlord Sir John Chandos. Charles is killed in action, ending the Blois pretensions in Brittany.
- 1365 – John V is recognized as Duke of Brittany and Jeanne de Penthievre gives up any claim to the duchy in the Treaty of Guérande. Surprisingly, the new duke declares himself as a vassal, not to the English king who helped him, but to king Charles V of France.
Read more about this topic: Breton War Of Succession