Counts and dukes of Penthièvre

In the 11th and 12th centuries the Countship of Penthièvre (Breton: Penteur) in Brittany (now in the department of Côtes-d'Armor) belonged to a branch of the sovereign House of Brittany. It initially belonged to the House of Rennes. Geoffrey I, Duke of Brittany, gave it to his brother Eudes in 1035, and his descendants formed a cadet branch of the ducal house.

The geographical region of Brittany that constituted the holdings of Penthièvre correlate closely with the territories that constituted the early Breton kingdom of Domnonée.

The history of the title Count of Penthièvre included frequent dispossessions and restorations. Henri d'Avaugour, heir of this family, was dispossessed of the countship in 1235. The Duke of Brittany, Pierre Mauclerc, founder of the Breton House of Dreux, gave it as dowry to his daughter, Yolande, on her marriage in 1238 to Hugh XI of Lusignan, Count of La Marche. John I, Duke of Brittany, Yolande's brother, seized the countship on her death in 1272. After the Breton War of Succession the title was dispossessed twice by the reigning Dukes of Brittany, once by John V and another time by Francis II.

Disputed Heirs to the Ducal Crown of Brittany

In 1337 Joan the Lame, Duchess of Brittany, brought Penthièvre to her husband, Charles de Châtillon, Count of Blois. Joan was the daughter of Guy de Penthièvre, the brother of John III.

When John III died a dispute emerged regarding the inheritance of the Duchy of Brittany. John III had tried to prevent the inheritance of the Duchy by his half brother John of Montfort. Joanna and Charles claimed the Ducal crown and were subsequently proclaimed the Duchess and Duke of Brittany, which John of Montfort also claimed. Their dispute prompted the Breton War of Succession. In 1352, during that war, the Estates of Brittany were established. In 1364, Joan and Charles lost the Breton civil war decisively; while they lost the duchy, they were permitted to keep Penthièvre, and Joan was permitted to keep the empty title Duchess of Brittany until her death.

Under the Treaty of Guerande, Joanna was permitted to retain the title Duchess of Brittany as a titulary and she recognized John IV, John of Montfort's son, as the undisputed Duke. When John IV went into exile in England in 1373, Charles V of France named his brother Louis, Duke of Anjou lieutenant-general of Brittany. Louis was also a son-in-law of Joanna de Penthièvre. Under the Treaties of Guerande (1365 and 1381), in the event the House of Montfort failed to produce a male heir to the Duchy of Brittany, the senior male heir of Joanna would be recognized as Duke. (This provision of the treaty was never activated; the House of Montfort would eventually merge the ducal crown into the crown of France.)

Joanna died in 1384 and left Penthièvre to her oldest son, Jean de Blois (1340–1404). In turn, Jean de Blois left Penthièvre to his son, Olivier (1389–1433) who would forfeit it to the Duke of Brittany in 1420.

In 1420, Duke John the Wise was kidnapped by the Dowager Countess of Penthièvre, the wife of Jean de Blois, and her son Olivier. John's wife, Joan of France, besieged the rebels and set free her husband. The freed Duke confiscated the Penthièvres' goods.

Olivier and his brother Jean de Blois (1393–1454) died childless, passing the recovered countship to Nicole de Blois (1424–1480), daughter of their brother Charles, seigneur of Avaugour (1396–1434).

In 1437 Nicole married Jean II de Brosse. She was deprived of Penthièvre by Francis II, Duke of Brittany in 1465, thus undermining the Penthièvre family's position in the country. In 1488, at the death of the last Breton duke, Francis II, the head of the Penthièvre family was Jean de Brosse (died 1502), grandson of Nicole de Blois, who asserted his family's claim to the duchy, but Francis' daughter Anne succeeded.

As Dukes of Penthièvre

The countship of Penthièvre was restored to Sebastian of Luxemburg, heir of the Brosse family through his mother, Charlotte de Brosse (1506-1540), great-granddaughter of Nicole de Blois through her son Jean (d. 1502) and grandson Rene (1470-1524). The countship was erected for him into a duchy in the peerage of France in 1569. Afterwards it was held by Sebastian's daughter, Marie de Luxembourg, (1562-1623), who also became Duchess of Mercœur by marriage.

Philippe Emmanuel, Duke of Mercœur, brother-in-law of Henry III of France (last living male-line grandson of Claude, Duchess of Brittany), and a leader of the Catholic League, was made governor of Brittany by the king in 1582. Invoking the hereditary rights of his wife, Marie de Luxembourg, he endeavoured to make himself independent in that province from 1589 onwards, and organized a government at Nantes, proclaiming their young son, Philippe de Lorraine-Mercœur, (d. 1590), "prince and duke of Brittany". He allied with Spain and defeated Henry IV of France's attempts to subjugate Brittany until 20 March 1598 when Mercœur was forced to surrender and subsequently went in exile to Hungary. Philippe died young, leaving his sister, Françoise de Lorraine-Mercœur the duchy of Penthièvre.

Later dukes from various houses

The Duchess of Vendôme's grandson, Louis Joseph, duc de Vendôme, inherited Penthièvre in 1669, but it was taken from him by decree in 1687 and adjudged to Anne Marie de Bourbon, Princess de Princess de Conti. In 1696, it was sold to Louis-Alexandre de Bourbon, Count de Toulouse, whose son, Louis de Bourbon, bore the title Duke de Penthièvre. This title passed by inheritance to the House of Orléans.

Counts of Penthièvre

House de Rennes

Eudes (1035–1079), son of Geoffrey I, Duke of Brittany
Geoffrey I (1079–1093), son of Eudes
Stephen I (1093–1125), son of Eudes, brother of Geoffrey I
Geoffrey II (1125–1148), son of Stephen I
Rivallo (1148–1162), son of Geoffrey II
Stephen II (1162–1164), son of Rivallo
Geoffrey III (1164–1177), son of Geoffrey II, brother of Stephen II
Alan I (1177–1212), cousin of Geoffrey III, grandson of Stephen I through his son Henry, called Henry I
Henry II of Avagour (1212–1230), son of Alan I, was dispossessed of Penthièvre by Peter I, Duke of Brittany, who gave it to his daughter Yolande on her marriage to Hugh XI of Lusignan

Lords of Avaugour

Alan II (1230–1267), son of Henry II
Henry III (1267–1304), son of Alan II
Henry IV (1301–1334), son of Henry III
Joan (1334–1384), granddaughter of Henry IV

Capetian House of Dreux

Peter Mauclerc (1230–1237), son of Robert II of Dreux
Yolande (1237-1272), daughter of Peter
John I (1272–1286), son of Peter
John II (1286–1305), son of John I
Arthur II (1305–1312), son of John II
Guy (1312–1331), son of Arthur II
Joan (1331–1384), Countess of Penthièvre suo jure; daughter of Guy, granddaughter of Henry IV of Avagour, married Charles de Blois-Châtillon, lost Breton War of Succession, but retained the county with all rights under the Treaty of Guerande of 1365

House of Blois-Châtillon

John III (1384–1404), son of Joan; his widow would join in attempting the abduction and imprisonment of the duke of Brittany, only to be imprisoned herself by the duchess.
Olivier (1404–1433), son of John III - lost the countship and the rights of Penthièvre to the duke of Brittany after attempting his imprisonment in 1420, and presumed overthrow.
John IV (1433–1454), son of John III, brother of Olivier - some aspects of Penthièvre were restored.
Nicole (1454–1479), niece of John IV, married Jean II de Brosse