Paternal Family Tree: Capet
Maternal Family Tree: Tomasina Morosini
In August 1396 [his father] John Montfort V Duke Brittany [aged 6] and [his mother] Joan Valois Duchess Brittany [aged 5] were married. She by marriage Duchess Brittany 1341 War of Sucession. She the daughter of [his grandfather] Charles "Beloved Mad" VI King France [aged 27] and [his grandmother] Isabeau Wittelsbach Queen Consort France [aged 26]. He the son of John Montfort V Duke Brittany [aged 57] and Joanna of Navarre Queen Consort England [aged 26]. They were second cousins. He a great x 3 grandson of King Henry III of England. She a great x 5 granddaughter of King Henry III of England.
On 14th May 1414 Francis Montfort I Duke Brittany was born to John Montfort V Duke Brittany [aged 24] and Joan Valois Duchess Brittany [aged 23]. He a great x 4 grandson of King Henry III of England. Coefficient of inbreeding 2.84%.
Before 4th August 1430 Philip Valois I Duke Brabant [aged 26] and [his future wife] Yolande Valois Anjou Duchess Brabant Duchess Brittany [aged 18] were married. She by marriage Duchess Brabant. She the daughter of King Louis of Naples and [his future mother-in-law] Yolande Barcelona Queen Consort Naples [aged 48]. He the son of Anthony Valois Duke Brabant and Jeanne Luxembourg Duchess Brabant. They were second cousins. He a great x 3 grandson of King Edward I of England. She a great x 5 granddaughter of King Henry III of England.
In August 1431 Francis Montfort I Duke Brittany [aged 17] and Yolande Valois Anjou Duchess Brabant Duchess Brittany [aged 19] were married. She by marriage Duchess Brittany. She the daughter of King Louis of Naples and Yolande Barcelona Queen Consort Naples [aged 49]. He the son of John Montfort V Duke Brittany [aged 41] and Joan Valois Duchess Brittany [aged 40]. They were second cousin once removed. He a great x 4 grandson of King Henry III of England. She a great x 5 granddaughter of King Henry III of England.
On 27th September 1433 [his mother] Joan Valois Duchess Brittany [aged 42] died.
On 12th November 1434 [his brother-in-law] Louis Valois Anjou III Duke Anjou [aged 31] died. His brother René [aged 25] succeeded I Duke Anjou. Isabella Metz Duchess Anjou I Duchess Lorraine [aged 34] by marriage Duchess Anjou.
In 1440 [his wife] Yolande Valois Anjou Duchess Brabant Duchess Brittany [aged 28] died.
On 29th August 1442 [his father] John Montfort V Duke Brittany [aged 52] died. His son Francis [aged 28] succeeded I Duke Brittany.
On 30th August 1442 Francis Montfort I Duke Brittany [aged 28] and Isabella Stewart Duchess Brittany [aged 16] were married. She by marriage Duchess Brittany. She the daughter of King James I of Scotland and Joan Beaufort Queen Consort Scotland [aged 38]. He the son of John Montfort V Duke Brittany [deceased] and Joan Valois Duchess Brittany. They were half fourth cousin once removed. He a great x 4 grandson of King Henry III of England. She a great x 2 granddaughter of King Edward III of England.
In 1443 [his daughter] Margaret Montfort Duchess Brittany was born to Francis Montfort I Duke Brittany [aged 28] and [his wife] Isabella Stewart Duchess Brittany [aged 17]. She a great x 3 granddaughter of King Edward III of England. She married before 29th June 1463 her first cousin once removed Francis Montfort II Duke Brittany and had issue.
In August 1443 John Beaufort 1st Duke of Somerset [aged 40] landed 7000 men at Cherbourg [Map] and then marched south. His campaign achieved little being bought off by Francis Montfort I Duke Brittany [aged 29]. He marched through Maine [Map] then returned to England in the winter of 1443.
The Deeds of the Dukes of Normandy
The Gesta Normannorum Ducum [The Deeds of the Dukes of Normandy] is a landmark medieval chronicle tracing the rise and fall of the Norman dynasty from its early roots through the pivotal events surrounding the Norman Conquest of England. Originally penned in Latin by the monk William of Jumièges shortly before 1060 and later expanded at the behest of William the Conqueror, the work chronicles the deeds, politics, battles, and leadership of the Norman dukes, especially William’s own claim to the English throne. The narrative combines earlier historical sources with firsthand information and oral testimony to present an authoritative account of Normandy’s transformation from a Viking settlement into one of medieval Europe’s most powerful realms. William’s history emphasizes the legitimacy, military prowess, and governance of the Norman line, framing their expansion, including the conquest of England, as both divinely sanctioned and noble in purpose. Later chroniclers such as Orderic Vitalis and Robert of Torigni continued the history, extending the coverage into the 12th century, providing broader context on ducal rule and its impact. Today this classic work remains a foundational source for understanding Norman identity, medieval statesmanship, and the historical forces that reshaped England and Western Europe between 800AD and 1100AD.
Available at Amazon in eBook and Paperback format.
In 1444 [his daughter] Marie Montfort was born to Francis Montfort I Duke Brittany [aged 29] and [his wife] Isabella Stewart Duchess Brittany [aged 18]. She a great x 3 granddaughter of King Edward III of England.
On 16th August 1445 [his sister-in-law] Margaret Stewart Dauphine of France [aged 20] died at Châlons-en-Champagne [Map]. She was buried at the Church of Saint-Laon Thouars.
On 12th February 1449 Sigismund Habsburg 4th Duke Austria [aged 21] and [his sister-in-law] Eleanor Stewart Duchess Austria [aged 16] were married at Merano. She by marriage Duchess Austria. She the daughter of King James I of Scotland and [his mother-in-law] Joan Beaufort Queen Consort Scotland. He the son of Frederick "Empty Pockets" Habsburg 4th Duke Austria and Anna of Brunswick-Wolfenbüttel Duchess Austria.
On 3rd July 1449 [his brother-in-law] King James II of Scotland [aged 18] and Mary of Guelders Queen Consort Scotland [aged 15] were married at Holyrood Abbey, Holyrood. She the daughter of Arnold Egmont Duke Guelders [aged 38] and Catherine de la Marck [aged 32]. He the son of King James I of Scotland and [his mother-in-law] Joan Beaufort Queen Consort Scotland. They were fourth cousin once removed. He a great x 2 grandson of King Edward III of England.
On 13th October 1494 [his former wife] Isabella Stewart Duchess Brittany [aged 68] died.
Kings Wessex: Great x 11 Grand Son of King Edmund "Ironside" I of England
Kings Godwinson: Great x 11 Grand Son of King Harold II of England
Kings England: Great x 4 Grand Son of King Henry III of England
Kings Scotland: Great x 9 Grand Son of King Malcolm III of Scotland
Kings France: Grand Son of Charles "Beloved Mad" VI King France
Kings Duke Aquitaine: Great x 15 Grand Son of Ranulf I Duke Aquitaine
Kings Spain: Great x 7 Grand Son of Alfonso II King Aragon
Great x 4 Grandfather: John "The Red" Capet I Duke Brittany 
3 x Great Grandson of King David I of Scotland
Great x 3 Grandfather: John II Duke Brittany 3 x Great Grandson of Alfonso VII King Castile VII King Leon
Great x 4 Grandmother: Blanche "Navarre" Blois Duchess Brittany 
2 x Great Granddaughter of Alfonso VII King Castile VII King Leon
Great x 2 Grandfather: Arthur II Duke Brittany Grandson of King Henry III of England
Great x 4 Grandfather: King Henry III of England 
son of King John of England
Great x 3 Grandmother: Beatrice Plantagenet daughter of King Henry III of England
Great x 4 Grandmother: Eleanor of Provence Queen Consort England 
Great Granddaughter of Alfonso II King Aragon
Great x 1 Grandfather: John Montfort IV Duke Brittany Great Grandson of King Henry III of England
Great x 4 Grandfather: John Capet I Count Dreux 6 x Great Grandson of Hugh I King of the Franks
Great x 3 Grandfather: Robert Capet IV Count Dreux 7 x Great Grandson of Hugh I King of the Franks
Great x 4 Grandmother: Marie Dampierre Countess Dreux 
Great x 2 Grandmother: Yolande of Dreux Queen of Scotland 5 x Great Granddaughter of King Henry I "Beauclerc" England
Great x 4 Grandfather: Jean Montfort 3 x Great Grandson of King Henry I "Beauclerc" England
Great x 3 Grandmother: Beatrice Montfort Countess Dreux 4 x Great Granddaughter of King Henry I "Beauclerc" England
Great x 4 Grandmother: Jeanne Chateaudun
Grandfather: John Montfort V Duke Brittany 2 x Great Grandson of King Henry III of England
Great x 4 Grandfather: Guy Dampierre Count Flanders 4 x Great Grandson of King William "Conqueror" I of England
Great x 3 Grandfather: Robert Dampierre III Count Flanders 5 x Great Grandson of King William "Conqueror" I of England
Great x 4 Grandmother: Mathilde Bethune
Great x 2 Grandfather: Louis Dampierre I Count Nevers 6 x Great Grandson of King William "Conqueror" I of England
Great x 4 Grandfather: Odo Burgundy 5 x Great Grandson of King William "Conqueror" I of England
Great x 3 Grandmother: Yolande Burgundy II Countess Nevers and Flanders 6 x Great Granddaughter of King William "Conqueror" I of England
Great x 4 Grandmother: Matilda Countess of Auxerre
Great x 1 Grandmother: Joanna of Flanders Duchess Brittany 7 x Great Granddaughter of King William "Conqueror" I of England
Great x 4 Grandfather: Manasses V Count Rethel 9 x Great Grandson of King Edward "Elder" of the Anglo Saxons
Great x 3 Grandfather: Hugh IV Count Rethel 10 x Great Grandson of King Edward "Elder" of the Anglo Saxons
Great x 2 Grandmother: Joan Rethel Countess Nevers and Rethel 11 x Great Granddaughter of King Edward "Elder" of the Anglo Saxons
father: John Montfort V Duke Brittany Great Grandson of King John "The Good" II of France
Great x 4 Grandfather: King Philip III of France son of King Louis IX of France
Great x 3 Grandfather: Louis I Count Évreux son of King Philip III of France
Great x 4 Grandmother: Maria of Brabant Queen Consort France 3 x Great Granddaughter of King Stephen I England
Great x 2 Grandfather: Philip "Noble" III King Navarre Grandson of King Philip III of France
Great x 4 Grandfather: Philip Artois Great Grandson of King Louis VIII of France
Great x 3 Grandmother: Margaret Artois Countess Évreux Great Granddaughter of King Henry III of England
Great x 4 Grandmother: Blanche Capet Granddaughter of King Henry III of England
Great x 1 Grandfather: Charles "Bad" II King Navarre Grandson of Louis X King France I Navarre
Great x 4 Grandfather: King Philip IV of France son of King Philip III of France
Great x 3 Grandfather: Louis X King France I Navarre son of King Philip IV of France
Great x 4 Grandmother: Joan Blois I Queen Navarre Great Granddaughter of King Louis VIII of France
Great x 2 Grandmother: Joan Capet II Queen Navarre daughter of Louis X King France I Navarre
Great x 4 Grandfather: Robert II Duke Burgundy 5 x Great Grandson of King William "Conqueror" I of England
Great x 3 Grandmother: Margaret of Burgundy Queen Consort France Granddaughter of King Louis IX of France
Great x 4 Grandmother: Agnes Capet Duchess Burgundy daughter of King Louis IX of France
Grandmother: Joanna of Navarre Queen Consort England Granddaughter of King John "The Good" II of France
Great x 4 Grandfather: Charles Valois I Count Valois son of King Philip III of France
Great x 3 Grandfather: King Philip "Fortunate" VI of France Grandson of King Philip III of France
Great x 4 Grandmother: Margaret Capet Countess Valois Great Granddaughter of King Louis VIII of France
Great x 2 Grandfather: King John "The Good" II of France son of King Philip "Fortunate" VI of France
Great x 4 Grandfather: Robert II Duke Burgundy 5 x Great Grandson of King William "Conqueror" I of England
Great x 3 Grandmother: Joan "Lame" Burgundy Queen Consort France Granddaughter of King Louis IX of France
Great x 4 Grandmother: Agnes Capet Duchess Burgundy daughter of King Louis IX of France
Great x 1 Grandmother: Joan Valois Queen Consort Navarre daughter of King John "The Good" II of France
Great x 4 Grandfather: Henry Luxembourg VII Holy Roman Emperor 
5 x Great Grandson of King William "Conqueror" I of England
Great x 3 Grandfather: King John I of Bohemia 6 x Great Grandson of King William "Conqueror" I of England
Great x 4 Grandmother: Margaret Brabant Countess Luxemburg and Namur
Great x 2 Grandmother: Bonne Luxembourg Queen Consort France 7 x Great Granddaughter of King William "Conqueror" I of England
Great x 4 Grandfather: King Wenceslaus II of Bohemia and Poland 6 x Great Grandson of King Harold II of England
Great x 3 Grandmother: Queen Elizabeth of Bohemia 7 x Great Granddaughter of King Harold II of England
Great x 4 Grandmother: Queen Judith of Bohemia and Poland 12 x Great Granddaughter of King Alfred "The Great" of Wessex
Francis Montfort I Duke Brittany Grandson of Charles "Beloved Mad" VI King France
Great x 4 Grandfather: Charles Valois I Count Valois son of King Philip III of France
Great x 3 Grandfather: King Philip "Fortunate" VI of France Grandson of King Philip III of France
Great x 4 Grandmother: Margaret Capet Countess Valois Great Granddaughter of King Louis VIII of France
Great x 2 Grandfather: King John "The Good" II of France son of King Philip "Fortunate" VI of France
Great x 4 Grandfather: Robert II Duke Burgundy 5 x Great Grandson of King William "Conqueror" I of England
Great x 3 Grandmother: Joan "Lame" Burgundy Queen Consort France Granddaughter of King Louis IX of France
Great x 4 Grandmother: Agnes Capet Duchess Burgundy daughter of King Louis IX of France
Great x 1 Grandfather: King Charles V of France son of King John "The Good" II of France
Great x 4 Grandfather: Henry Luxembourg VII Holy Roman Emperor 5 x Great Grandson of King William "Conqueror" I of England
Great x 3 Grandfather: King John I of Bohemia 6 x Great Grandson of King William "Conqueror" I of England
Great x 4 Grandmother: Margaret Brabant Countess Luxemburg and Namur
Great x 2 Grandmother: Bonne Luxembourg Queen Consort France 7 x Great Granddaughter of King William "Conqueror" I of England
Great x 4 Grandfather: King Wenceslaus II of Bohemia and Poland 6 x Great Grandson of King Harold II of England
Great x 3 Grandmother: Queen Elizabeth of Bohemia 7 x Great Granddaughter of King Harold II of England
Great x 4 Grandmother: Queen Judith of Bohemia and Poland 12 x Great Granddaughter of King Alfred "The Great" of Wessex
Grandfather: Charles "Beloved Mad" VI King France son of King Charles V of France
Great x 4 Grandfather: Robert Bourbon 1st Count Clermont son of King Louis IX of France
Great x 3 Grandfather: Louis Bourbon I Duke Bourbon Grandson of King Louis IX of France
Great x 4 Grandmother: Beatrice Burgundy 6 x Great Granddaughter of King William "Conqueror" I of England
Great x 2 Grandfather: Peter Bourbon Duke Bourbon Great Grandson of King Louis IX of France
Great x 4 Grandfather: John of Avesnes II Count Hainaut II Count Holland 3 x Great Grandson of King Stephen I England
Great x 3 Grandmother: Mary Hainaut Duchess Bourbon 4 x Great Granddaughter of King Stephen I England
Great x 4 Grandmother: Philippa Luxembourg Countess Hainaut and Holland 5 x Great Granddaughter of King William "Conqueror" I of England
Great x 1 Grandmother: Joanna Bourbon Queen Consort France Great Granddaughter of King Philip III of France
Great x 4 Grandfather: King Philip III of France son of King Louis IX of France
Great x 3 Grandfather: Charles Valois I Count Valois son of King Philip III of France
Great x 4 Grandmother: Isabella Barcelona Queen Consort France Great Granddaughter of Alfonso II King Aragon
Great x 2 Grandmother: Isabella Valois Duchess Bourbon Granddaughter of King Philip III of France
Great x 4 Grandfather: Guy Chatillon IV Count Saint Pol 3 x Great Grandson of King Stephen I England
Great x 3 Grandmother: Mahaut Chatillon Countess Valois Great Granddaughter of King Henry III of England
Great x 4 Grandmother: Marie Capet Granddaughter of King Henry III of England
mother: Joan Valois Duchess Brittany daughter of Charles "Beloved Mad" VI King France
Great x 4 Grandfather: Louis "Strict" Wittelsbach II Duke Upper Bavaria 
2 x Great Grandson of King Henry "Curtmantle" II of England
Great x 3 Grandfather: Louis Wittelsbach IV Holy Roman Emperor 3 x Great Grandson of King Henry "Curtmantle" II of England
Great x 4 Grandmother: Matilda Habsburg Duchess Bavaria 12 x Great Granddaughter of King Alfred "The Great" of Wessex
Great x 2 Grandfather: Stephen Wittelsbach II Duke Bavaria 4 x Great Grandson of King Henry "Curtmantle" II of England
Great x 3 Grandmother: Beatrix Świdnica Holy Roman Empress
Great x 1 Grandfather: Stephen "Magnificient Fop" Wittelsbach III Duke Bavaria 3 x Great Grandson of King Louis VIII of France
Great x 4 Grandfather: Peter III King Aragon Great Grandson of Alfonso II King Aragon
Great x 3 Grandfather: Frederick III King Sicily 2 x Great Grandson of Alfonso II King Aragon
Great x 2 Grandmother: Elisabeth Barcelona Duchess Bavaria 2 x Great Granddaughter of King Louis VIII of France
Great x 4 Grandfather: Charles II King Naples Grandson of King Louis VIII of France
Great x 3 Grandmother: Eleanor Capet Great Granddaughter of King Louis VIII of France
Great x 4 Grandmother: Mary of Hungary Queen Consort Naples 6 x Great Granddaughter of King Harold II of England
Grandmother: Isabeau Wittelsbach Queen Consort France 4 x Great Granddaughter of King Louis VIII of France
Great x 4 Grandfather: Matteo I Visconti
Great x 3 Grandfather: Stephano Visconti
Great x 4 Grandmother: Bonacossa Borri
Great x 2 Grandfather: Bernabò Visconti
Great x 3 Grandmother: Valentina Doria
Great x 1 Grandmother: Taddea Visconti Duchess Bavaria
Great x 3 Grandfather: Mastino II della Scala
Great x 2 Grandmother: Beatrice Regina della Scala
Great x 4 Grandfather: Jacopo I da Carrara
Great x 3 Grandmother: Taddea da Carrara
Great x 4 Grandmother: Anna Gradenigo