The Duchy of Brittany was a medieval feudal state that existed between approximately 939 and 1547. Its territory covered the northwestern peninsula of Europe, bordered by the Atlantic Ocean 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. The Duchy, in the 10th and 11th centuries, was politically unstable, with the dukes holding only limited power outside their own personal lands. The Duchy 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.
The Battle of Auray took place on 29 September 1364 at the Breton-French town of Auray. This battle was the decisive confrontation of the Breton War of Succession, a part of the Hundred Years' War.
The War of the Breton Succession was a conflict between the Counts of Blois and the Montforts of Brittany for control of the Sovereign Duchy of Brittany, then a fief of the Kingdom of France. It was fought between 1341 and 12 April 1365. It is also known as the War of the Two Jeannes due to the involvement of two rival duchesses of that name.
John of Montfort, sometimes known as John IV of Brittany, and 6th Earl of Richmond from 1341 to his death. He was the son of Arthur II, Duke of Brittany and his second wife, Yolande de Dreux. He contested the inheritance of the Duchy of Brittany by his niece, Joan of Penthièvre, which led to the War of the Breton Succession, which in turn evolved into being part of the Hundred Years' War between England and France. John's patron in his quest was King Edward III of England. He died in 1345, 19 years before the end of the war, and the victory of his son John IV over Joan of Penthièvre and her husband, Charles of Blois.
Charles of Blois-Châtillon, nicknamed "the Saint", was the legalist Duke of Brittany from 1341 until his death, via his marriage to Joan, Duchess of Brittany and Countess of Penthièvre, holding the title against the claims of John of Montfort. The cause of his possible canonization was the subject of a good deal of political maneuvering on the part of his cousin, Charles V of France, who endorsed it, and his rival, Montfort, who opposed it. The cause fell dormant after Pope Gregory XI left Avignon in 1376, but was revived in 1894. Charles of Blois was beatified in 1904.
John IV the Conqueror KG, was Duke of Brittany and Count of Montfort from 1345 until his death and 7th Earl of Richmond from 1372 until his death.
John V, sometimes numbered as VI, bynamed John the Wise, was Duke of Brittany and Count of Montfort from 1399 to his death. His rule coincided with the height of the Hundred Years' War between England and France. John's reversals in that conflict, as well as in other internal struggles in France, served to strengthen his duchy and to maintain its independence.
Joanna of Flanders was Duchess of Brittany by her marriage to John of Montfort. Much of her life was taken up in defense of the rights of her husband and, later, son to the dukedom, which was challenged by the House of Blois during the War of the Breton Succession. Known for her fiery personality, Joanna led the Montfort's cause after her husband had been captured by King Phillip, and began the fight-back. There, she displayed considerable skill as a military leader. Aside from her astounding skills as a military leader, Joanna functioned as a leader that the people loved.
The first phase of the Hundred Years' War between England and France lasted from 1337 to 1360. It is sometimes referred to as the Edwardian War because it was initiated by King Edward III of England, who claimed the French throne in defiance of King Philip VI of France. The dynastic conflict was caused by disputes over the French feudal sovereignty over Aquitaine and the English claims over the French royal title. The Kingdom of England and its allies dominated this phase of the war, and Edward's sovereignty over Aquitaine was confirmed in the Treaty of Brétigny (1360), although he renounced his claim to the French throne.
The House of Rohan is a Breton family of viscounts, later dukes and princes in the French nobility, coming from the locality of Rohan in Brittany. Their line descends from the viscounts of Porhoët and is said to trace back to the legendary Conan Meriadoc. Through the Porhoët family, the Rohans are related to the Dukes of Brittany, with whom the family intermingled again after its inception. During the Middle Ages, it was one of the most powerful families in the Duchy of Brittany. The Rohans developed ties with the French and English royal houses as well, and they played an important role in French and European history.
Olivier V de Clisson, nicknamed "The Butcher", was a Breton soldier, the son of Olivier IV de Clisson. His father had been put to death by the French in 1343 on the suspicion of having willingly given up the city of Vannes to the English.
The battle of Brest, sometimes called the battle of the River Penfeld, was an action in 1342 between an English squadron of converted merchant ships and that of a mercenary galley force from Genoa fighting for the Franco-Breton faction of Charles of Blois during the Breton War of Succession, a side conflict of the Hundred Years War.
The Battle of Champtoceaux, often called the Battle of l'Humeau, was the opening action of the 23-year-long War of the Breton Succession, a dynastic conflict in the Sovereign Duchy of Brittany which became inevitably embroiled in the Hundred Years War between England and France. This battle should have decided the war at a stroke, as John of Montfort, the leader of one faction, was made prisoner. However his wife, Joanna of Flanders, and young son John escaped imprisonment. Their escape and continued support from his ally, England, allowed continued resistance to flourish and eventually turn the tide.
Jeanne de Clisson (1300–1359), also known as Jeanne de Belleville and the Lioness of Brittany, was a French/Breton noblewoman who became a privateer to avenge her husband after he was executed for treason by King Philip VI of France. She crossed the English Channel targeting French ships and often slaughtering their crew. It was her practice to leave at least one sailor alive to carry her message of vengeance.
The French–Breton War lasted from 1487 to 1491. The cause of this war was the approaching death of the Breton Duke Francis II of Brittany, who had no clear successor. If not resolved, this meant a resumption of issues from a previous War of the Breton Succession (1341–1364), which had rival claimants allying with England or France, resulting in an ambiguous peace treaty that failed to prevent future succession disputes.
The Truce of Malestroit was signed on 19 January 1343 between Edward III of England and Philip VI of France, in the chapelle de la Madeleine in Malestroit. After the signing of this truce, the English sovereign and his troops left Bretagne for England.
Herve VII of Léon was a Breton lord, son of Herve VI, Lord of Léon and his wife Joanna of Montmorency. Also known as Herve. He succeeded his father as Lord of Léon in 1337. He was also Lord of Noyon-sur-Andelle. The Lords of Léon were a junior branch of the Viscounts of Léon which was founded by Harvey I, second son of Guihomar IV, Viscount of Léon. Herve VII won fame during the War of the Breton Succession.
John I, was Count of Penthièvre and Viscount of Limoges from 1364 to 1404, and the Penthièvre claimant to the Duchy of Brittany.
Olivier IV de Clisson (1300–1343), was a Breton Marche Lord and knight who became embroiled in the intrigue of Vannes and was subsequently executed by the King of France for perceived treason. He was the husband of Jeanne de Clisson who eventually became known as the Lioness of Brittany.
Amaury de Clisson (1304–1347), was a Breton knight who became the chief emissary for Jeanne de Penthièvre to the court of Edward III of England.
Bretons 
Kingdom of England 
Kingdom of France 
John of Montfort 
Robert III of Artois †
Charles of Blois 
Olivier IV de Clisson 
