The Duchy of Brittany (Breton: Dugelezh Breizh [dyˈɡɛːlɛs ˈbrɛjs]; French: Duché de Bretagne) was a medieval feudal state that existed between approximately 939 and 1547. Its territory covered the northwestern peninsula of France, bordered by the Bay of Biscay to the west, and the English Channel to the north. It was also less definitively bordered by the river Loire to the south, and Normandy, and other French provinces, to the east. The duchy was established after the expulsion of Viking armies from the region around 939. In the 10th and 11th centuries, it was politically unstable, with the dukes holding only limited power outside their own personal lands. The Duchy of Brittany had mixed relationships with the neighbouring Duchy of Normandy, sometimes allying itself with Normandy, and at other times, such as the Breton–Norman War, entering into open conflict.
Henry II of England invaded Brittany in the mid-12th century and became Count of Nantes in 1158 under a treaty with Duke Conan IV. Henry's son, Geoffrey, became Duke through his marriage to Constance, the hereditary Duchess. The Angevins remained in control until the collapse of their empire in northern France in 1204. The French Crown maintained its influence over the duchy for the rest of the 13th century. Monastic orders supported by the Breton aristocracy spread across the duchy in the 11th and 12th centuries, and in the 13th, the first of the mendicant orders established themselves in Brittany's major towns. A civil war broke out in the 14th century, as rival claimants for the duchy vied for power during the Breton War of Succession, with different factions supported by England and France.
The independent sovereign nature of the duchy began to come to an end upon the death of its duke, Francis II, in 1488. The Duchy was inherited by his daughter, Anne, but King Charles VIII of France had her existing marriage annulled and then married her himself. As a result, the King of France acquired the title of Duke of Brittany – jure uxoris. The Ducal crown became united with the French crown in 1532 through a vote of the Estates of Brittany, after the death of Queen Claude of France, the last sovereign duchess. Her sons Francis III, Duke of Brittany and then Henry II of France would in any case have created a personal union on the death of their father.
Following the French Revolution, and as a result of the various republican forms of French government since 1792, the duchy was replaced by the French system of départements (or departments) which continues under the Fifth Republic of France. In modern times the departments have also joined into administrative regions although the administrative region of Brittany does not encompass the entirety of the medieval duchy. The movement for the reunification of Brittany calls for the restoration of the territorial integrity of the historic Duchy of Brittany as a region of the French Republic.
Background
Origins
The Duchy of Brittany that emerged in the early 10th century was influenced by several earlier polities. Prior to the expansion of the Roman Empire into the region, Gallic tribes had occupied the Armorican peninsula, dividing it into five regions that then formed the basis for the Roman administration of the area, and which survived into the period of the Duchy. These Gallic tribes – termed the Armorici in Latin – had close relationships with the Britonnes tribes in Roman Britain. Between the late 4th and the early 7th centuries, many of these Britonnes migrated to the Armorican peninsula, blending with the local people to form the later Britons, who eventually became the Bretons. The reasons for these migrations remain uncertain. These migrations from Britain contributed to Brittany's name.
Brittany fragmented into small, warring regna, kingdoms, each competing for resources. The Frankish Carolingian Empire conquered the region during the 8th century, starting around 748 taking the whole of Brittany by 799. The Carolingians tried to create a unitary administration around the centres of Rennes, Nantes, and Vannes using the local rulers, but the kings of Brittany's hold on the region remained tenuous. Carolingian technology and culture began to influence Brittany, and the church in Brittany also began to emulate the Frankish model.
The greatest influence on the later Duchy, however, was the formation of a unitary Brittany kingdom in the 9th century. In 831 Louis the Pious appointed Nominoe, the Count of Vannes, ruler of the Bretons, imperial missus, at Ingelheim in 831. After the death of Louis in 840, Nominoe rose to challenge the new emperor, Charles the Bald, emboldened in part by new Viking raids on the empire. Charles the Bald created the Marches of Neustria to defend Western Francia from the Bretons and the Vikings. Erispoe fought Charles the Bald, who felt that a quick attack would successfully challenge the new Breton leader. Erispoe won a victory at the Battle of Jengland and, under their Treaty of Angers in 851, Brittany's independence was secured.
The new kingdom proved fragile and collapsed under Viking attack. In 853 the Viking Godfried left the Seine with his fleet, sailed around the Breton peninsula and sacked Nantes. Erispoe entered into an alliance with the leader of another Viking fleet, Sidroc, who betrayed him, resulting in Erispoe's defeat at the hands of the Vikings. A weakened Erispoe ruled until 857 when he was assassinated and then followed as Breton ruler by his cousin and rival, Salomon, the Count of Rennes and Nantes. Viking raids continued. Alan I successfully defeated one wave of Vikings around 900, expanding the kingdom to include not only the Breton territories of Léon, Domnonée, Cornouaille, and the Vannetais, but also the Frankish counties of Rennes, Nantes, Coutances, and Avranches, as well as the western parts of Poitou and Anjou. Alan I's military success resulted in a period of peace from Viking invasions and few raids from the Vikings were recorded from 900 through to 907.
After Alan I's death in 907, Brittany was overrun once again by Vikings. Fulk the Red, Count of Anjou, is said to have occupied Nantes from 907 to 919 when he abandoned it to the invading Vikings. In 919, the great Viking fleet of Rognvaldr landed in Nantes, quickly coming to dominate the region. This invasion accelerated the exodus of Bretons, including that of the machtierns, "the local hereditary officers upon whom the civil administration depended". Among the refugees were Mathedoi, the Count of Poher, and his son Alan Barbetorte, the grandson of Alan I; they fled to England and lived in exile in the courts of Edward the Elder and Edward's son and successor Æthelstan. The Viking occupation of Brittany lasted until about 936. Little recorded history of this period is available until Alan Barbetorte returned in 937 to expel the Vikings and reestablish a version of the former Carolingian kingdom.
History
10th century
The Duchy of Brittany emerged after Alan Barbetorte's return to the region from England in 936. Barbetorte claimed the titles of the Count of Cornouaille and Nantes and, as Alan II, reigned as the new Brittonum dux. Using a network of small, defended towns and monastic sites, Alan pushed back the Viking advances. On 1 August 939, with the aid of Judicael Berengar, Count of Rennes, and Hugh I, Count of Maine, he defeated the Vikings in the Battle of Trans-la-Forêt, completing their expulsion from Brittany. Alan's duchy was smaller than the previous Kingdom of Brittany, as, despite gaining Magues and Tiffauges in the south, the dukes no longer ruled over the regions of Cotentin, Avranchin, and Mayenne. Alan paid homage to Louis IV of France for Brittany in 942. Despite some older Celtic influences, the new duchy was in many ways similar to the other, post-Carolingian states forming across the region. Over the coming decades, a network of powerful local lords emerged across Brittany, occupying motte and bailey castles and owing a loose feudal loyalty to the duke. The east of Brittany was the first to change, but the practices spread over the next fifty years to the more remote regions of the north- and south-west.
Alan II was also allied to Theobald I of Blois, the count of Chartres. Alan II had married Theobald's sister, Adelaide, giving Theobald influence all the way to Rennes. However Alan II's death left a void in Brittany leaving it vulnerable to encroachment by either the Normans or the Angevins. In turn the recently widowed Fulk II, Count of Anjou, Theobald's ally, married Alan II's widow. Upon his death, Alan II was succeeded by his son Drogo. Drogo's rule set the precedent for the role of a regent during the minority of a ducal heir. Throughout his reign, Drogo was under the shared regency of his uncle the Count of Blois, Theobald I (who entrusted the administration of the duchy to Wicohen, Archbishop of Dol, and the Count of Rennes Juhel Berengar as administrators), and his stepfather, the Fulk II, Count of Anjou.
Under Drogo, the duchy continued to experience political instability and he was unable to sustain his line. Drogo died in 958. Two of Alan II's illegitimate sons, Hoël and Guerich, attempted to act as Counts of Nantes and preserve their claim to duchy but were eventually unsuccessful. In 990 Juhel Berengar's son Conan I, the grandson of Pascweten, became Duke and the title passed to the House of Rennes. Conan I ruled for only two years and died fighting against his brother-in-law Fulk III, Count of Anjou at the Battle of Conquereuil on 27 June 992. He was succeeded by his oldest son Geoffrey I. Blois threatened Conan's succession. Duke Geoffrey I, a member of the House of Nantes, entered into a dynastic alliance with Richard II, Duke of Normandy in a diplomatic double marriage between the two houses. The church-sanctioned marriage ceremonies were held at Mont Saint-Michel. Geoffrey I married Hawise of Normandy, Richard II's sister; and Richard II married Judith of Brittany, Geoffrey I's sister and Conan I's daughter.
11th century
The 11th century was marked by a failed alliance with Normandy. William the Conqueror challenged the Breton dukes, and they formed an alliance with the French king.
The death of Geoffrey I, in 1008, allowed Richard II to intervene directly in Brittany during the minority of his nephew, Alan III, against rebellious counts who attempted to take advantage of the youthful duke. The guardianship would be reciprocated later when Alan III was named as one of the primary guardians of William of Normandy. By designating Alan III as a guardian of William, Robert I was "involving a close family member who would not compete with his heir". In his guardianship of Duke William, Alan III was allied with Count Gilbert and Robert II, Archbishop of Rouen, William's uncles. However, when Archbishop Robert died in 1037 instability surfaced. Alan III countered the instability by reinforcing the power of the Norman ducal house providing Robert I's two youngest brothers with land and title. However, by October 1, 1040, Alan III was killed by poison while besieging a rebel castle in Vimoutiers. Tension increased in Normandy following his death, with Count Gilbert dying shortly thereafter. A rival faction in the guardianship of Normandy emerged, one that would intervene in Brittany, suppressing Alan III's heir, Conan II, from claiming his inheritance.
At around eight years of age, Conan II succeeded his father Alan III as Duke of Brittany, with the ducal regency entrusted to Alan's brother Odo, Count of Penthièvre. However, by the time Conan II reached his majority at age sixteen, around 1048, Odo refused to relinquish power. During the dynastic conflict between uncle and nephew, Hoel of Cornouaille supported Odo in suppressing Conan's inheritance. Odo was Hoèl's brother-in-law as he was married to Hoel's sister Agnes of Cornouaille. By 1057, Conan II captured and imprisoned Odo. He came to terms with Hoèl of Cornouaille later that year. Conan II faced numerous threats posed by the pro-Norman faction in Brittany, including revolts sponsored by William, Duke of Normandy for whom Conan's father had served as Guardian. William supported challengers to Conan's authority, encouraging them to rebel against the Breton duke, his cousin. William continued courting the family of Odo, who was imprisoned. In response, Conan promoted his own legitimate claim as Duke of Normandy over William, as the Catholic Church began preferring legitimate heirs born in church-sanctioned marriage over out-of-wedlock issue. This rivalry led to war between Normandy and Brittany.
The 1064–1065 war between Brittany and Normandy (the Breton-Norman War) was sparked after Duke William supported the rebellion against Conan II led by Rivallon I of Dol. In 1065, before his invasion of Anglo-Saxon England, William of Normandy warned his rivals in Brittany and Anjou to abstain from any attacks on his duchy, on the grounds that his mission bore the papal banner. However, Conan II rebuffed the warning and declared that he would press any advantage against William. While William plotted to take the English crown, Conan consolidated his authority in Brittany and planned to take advantage of William's absence to invade Normandy. First, however, he needed to neutralize Anjou, another historic rival. Once Anjou was pacified he planned to advance into Maine and then into Normandy. However, during his 1066 siege of Angers, Conan was found dead after wearing poisoned riding gloves. Duke William was widely suspected of organising the assassination.