Breton Succession, 1341 – 1364
In 1341 the War of the Breton Succession broke out when the previous Duke died leaving progeny from two marriages. His heir was John III by his first marriage but he was childless, John selected as his heir a niece who in 1337 married Charles de Blois; he would be one of the contenders for the Duchy. He made his claims to Philip VI and became the French favourite for the rolr.
His opponent was his half-brother, John de Montfort, son of the old Duke’s second wife. John moved decisively seizing the capital Nantes and the treasury at Limoges, and went on to occupy Rennes and Vannes. He reached out to Edward III of England to support his claim.
Edward could not act because of the truce with France, but this did not prevent the French from invading a vassal state. They sieged Nantes and John de Montfort was forced to surrender by his ‘people’, he was imprisoned.
In 1342 his wife Joanna of Flanders had taken up the cause but she was besieged in Brest, An English army under the Earl of Northampton came to her rescue. He had just 1,350 men and some 250 small merchant vessels. On arrival he found a strong force of fourteen galleys holding the port, fortunately many of these had their crews ashore.
Northampton closed on the French fleet, three galleys panicked and escaped off to the open seas, the other eleven were overwhelmed and set fire. Northampton was reinforced by a further 800 men led by Robert of Artois.
Northampton was still heavily outnumbered but King Philip VI was concerned that Edward III was planning to invade Calais now that the truce was broken and withdrew much of his force to defend that port. His spies reported a build-up of forces in southern England, but these were in fact destined for Brest too, though there was a shortage of vessels to transport them anywhere.
Northampton later marched on the stronghold of Morlaix in the Finistère region of Brittany and set siege. Charles de Blois now had the support of 15,000 men and thus heavily outnumbered the English force. Northampton advised of his advance decided to break off the siege and march overnight to confront Charles.
Reports of the battle are quite vague but it appears that the English archers withstood two waves of attack from infantry and cavalry, but when they were running short of arrows they retreated in to a wood to make cavalry attacks less practical.
Charles led his force to relieve Morlaix and went on to take Rennes and Vannes. Late in the year Edward III arrived with his army in Brest and they marched to siege Vannes. The French were on the point of despatching an army to assist Charles, but before any engagements had commenced the two monarchs agreed a new truce until autumn 1346.
Vannes was taken under Papal control. The English had to administer the Montfort areas of control because John was still in prison, his wife had descended into madness and his son was still an infant. In 1343 was released against a large bond and his promise to remain in his eastern part of Brittany. He did retake control of Vannes but his territories began to wither, he was entirely reliant on English force and largesse.
In 1344 Charles de Blois took Quimper. His troops massacred between 1500 and 2000 civilians which would prove to tarnish is image. The English there were ransomed, the Bretons and Normans sent to Paris where they were executed for treason. John escaped to England.
Edward III repudiated the truce a year early, in the summer of 1345, and despatched a force under Northampton and John de Montfort. They were greeted with early success defeating Charles de Blois at Cadoret. But the key objective was to try to seize a port on the north coast of the peninsula for planned later landings. John de Montfort did try to recover Quimper to no effect. He was arrested by Philip VI and died later in 1345.
Over the next few years the English troops did start to make progress against Charles, finally capturing him in 1347. He was imprisoned in the Tower of London for five years. By then the English had control of Brest, Quimper and Vannes.
Edward had subsequently decided that his army should land in Normandy and his focus moved away from Brittany.
Edward signed the Treaty of Westminster in 1353, this recognised Charles de Blois as Duke of Brittany in return for ransom of 300,000 crowns and an in perpetuity alliance with England, the deal to be sealed by the marriage of John’s son, also called John, to Charles’ daughter, Mary.
Charles II of Navarre was concerned that the end of war between England and France would not be serve his own ambitions. He killed Philip’s negotiator, Charles de la Cerda, and as a result the treaty and marriage were never confirmed. Charles de Blois had however already been released and was back in Brittany.