Featured Article Summary #150

The siege of Hennebont happened between late May and late June 1342, when Charles of Blois led an unsuccessful attack on the fortified port of Hennebont, which was defended by Joanna of Montfort. This conflict was part of the Breton Civil War over who should control the Duchy of Brittany, and it was made more complicated by the ongoing Hundred Years’ War between France and England. France supported Charles of Blois, while England had promised military help to Joanna and her husband John of Montfort, the rival claimant. Charles’s forces first gained ground in eastern Brittany and captured John, prompting Joanna to focus her strength on defending Hennebont. When Charles arrived, an early French assault went badly and was driven back, with the Montfortists pursuing, causing heavy losses, and burning the French camp. Later attacks also failed, and although a French detachment tried to starve the town, English reinforcement by sea kept Hennebont holding out until Charles returned in July with stronger support, after which the Montfortists withdrew. Brittany was mostly run like it was independent, though its duke was a vassal of the French king. When Duke John III died in 1341, the duchy was contested between his niece Joan of Penthièvre (married to the French noble Charles of Blois) and his half-brother John of Montfort, with most nobles and clergy backing Charles. After John of Montfort quickly took control of many fortified towns, the French king declared Charles the rightful heir and sent a major army to support him, sparking the Breton Civil War. In late 1341, the French overran most of eastern Brittany, captured John of Montfort, and tried to persuade him to give up his claims in exchange for money and land in France. After John refused and was imprisoned, his wife Joanna took charge in western Brittany, recaptured key towns including Redon and pushed to secure Hennebont, using their young son as the faction’s figurehead. Seeing the Hundred Years’ War in progress, Joanna sent Amaury of Clisson to England to urge Edward III to help; this began Edward’s strategy of backing opponents of the French king, though English reinforcements were delayed by the Truce of Espléchin until 24 June 1342. In mid-April Charles advanced toward Rennes, where the local people took over the commander left behind by Joanna and surrendered to the French. An English force under Sir Walter Mauny arrived in western Brittany to hold key ports, but Charles soon detached troops to besiege Vannes and marched on Hennebont. Despite early attacks and fierce fighting, including one led by mercenaries against the town gates, the French assaults were repulsed and the Montfortists even burned the French camp; Joanna was said to have encouraged the defenders in full armour. Charles then settled into a formal siege, hoping starvation would force surrender, offered pardons to draw people back to France, but distrust grew after a betrayal of safe conduct; Mauny later reinforced Hennebont, and by late June the besiegers withdrew, with Charles also abandoning his siege of Auray. In late June and early July, the French sent over 10,000 men to renew the fighting in Brittany, quickly winning ground: Auray was abandoned, Vannes surrendered, and other towns switched to the French. Joanna judged Hennebont to be lost and left for Brest, but after English troops landed and relieved the area, Charles withdrew and later failed to relieve Morlaix. Fighting continued through further sieges and truces, until Charles of Blois was defeated and killed in 1364, and the civil war ended in 1365 with the Treaty of Guérande, while the wider Hundred Years’ War continued until 1453.