Biography of John Capet III Duke Brittany 1286-1341

John Capet III Duke Brittany was appointed III Duke Brittany 1221 Dreux.

In 1275 [his father] Arthur Capet Duke Brittany (age 13) and [his mother] Marie Limoges Duchess Brittany were married. She by marriage Duchess Brittany 1221 Dreux. He the son of [his grandfather] John Capet II Duke Brittany (age 36) and [his grandmother] Beatrice Plantagenet (age 32). They were third cousins. He a grandson of King Henry III of England.

On 8th March 1286 John Capet III Duke Brittany was born to Arthur Capet Duke Brittany (age 24) and Marie Limoges Duchess Brittany. He a great grandson of King Henry III of England.

On 1st December 1291 James "The Just" II King Aragon (age 24) and [his future wife] Isabella Ivrea Queen Consort Aragon (age 8) were married. She by marriage Queen Consort Aragon. She the daughter of Sancho IV King Castile IV King Leon (age 33) and Maria Molina Queen Consort Castile Queen Consort Leon. He the son of Peter III King Aragon and Constance Hohenstaufen Queen Consort Aragon (age 42). They were first cousin once removed. She a great x 4 granddaughter of King Henry "Curtmantle" II of England.

In or before 1295 [his father] Arthur Capet Duke Brittany (age 33) and [his step-mother] Yolande Capet Duchess Brittany (age 33) were married. She by marriage Duchess Brittany 1221 Dreux. She the daughter of Robert Capet IV Count Dreux and Beatrice Montfort Countess Dreux (age 46). He the son of [his grandfather] John Capet II Duke Brittany (age 55) and [his grandmother] Beatrice Plantagenet. They were third cousins. He a grandson of King Henry III of England. She a great x 5 granddaughter of King Henry I "Beauclerc" England.

In 1297 John Capet III Duke Brittany (age 10) and Isabelle Valois Duchess Brittany (age 5) were married. She by marriage Duchess Brittany 1221 Dreux. She the daughter of Charles Valois I Count Valois (age 26) and Margaret Capet Countess Valois (age 24). They were third cousins. He a great grandson of King Henry III of England. She a great x 4 granddaughter of King Henry "Curtmantle" II of England.

On 19th May 1305 William Hainault I Count Hainault III Count Avesnes III Count Holland II Count Zeeland (age 19) and [his sister-in-law] Joan Valois Countess Zeeland Holland Avesnes and Hainault (age 11) were married. She by marriage Countess Zeeland, Countess Holland, Countess Avesnes, Countess Hainault. She the daughter of [his father-in-law] Charles Valois I Count Valois (age 35) and [his mother-in-law] Margaret Capet Countess Valois. He the son of John Hainault II Count Hainault II Count Holland and Philippa Luxemburg Countess Hainault and Holland (age 53). They were fourth cousin once removed. He a great x 4 grandson of King Stephen I England. She a great x 4 granddaughter of King Henry "Curtmantle" II of England.

In 1307 Hugh Chatillon II Count Blois died. His son Guy succeeded I Count Blois. [his sister-in-law] Margaret Valois (age 12) by marriage Countess Blois.

In 1309 [his wife] Isabelle Valois Duchess Brittany (age 17) died.

In 1310 John Capet III Duke Brittany (age 23) and Isabella Ivrea Queen Consort Aragon (age 27) were married. She by marriage Duchess Brittany 1221 Dreux. She the daughter of Sancho IV King Castile IV King Leon and Maria Molina Queen Consort Castile Queen Consort Leon. They were fourth cousin once removed. He a great grandson of King Henry III of England. She a great x 4 granddaughter of King Henry "Curtmantle" II of England.

On 27th August 1312 [his father] Arthur Capet Duke Brittany (age 51) died.

On 7th September 1312 [his brother-in-law] Ferdinand IV King Castile IV King Leon (age 26) died. His son Alfonso (age 1) succeeded XI King Castile.

On 7th January 1325 Denis I King Portugal (age 63) died. His son Alfonso (age 33) succeeded IV King Portugal. [his sister-in-law] Beatrice Ivrea Queen Consort Portugal (age 32) by marriage Queen Consort Portugal.

In 1328 [his wife] Isabella Ivrea Queen Consort Aragon (age 45) died.

In 1329 John Capet III Duke Brittany (age 42) and Joan Savoy Duchess Brittany (age 19) were married. She by marriage Duchess Brittany 1221 Dreux. The difference in their ages was 23 years. She the daughter of Edward "Liberal" Savoy Count Savoy (age 45) and Blanche Burgundy Countess Savoy (age 41). They were second cousins. He a great grandson of King Henry III of England. She a great x 4 granddaughter of King Henry "Curtmantle" II of England.

In 1334 [his uncle] John Capet 4th Earl Richmond (age 68) died. His nephew John (age 47) succeeded 5th Earl Richmond.

On 30th April 1341 John Capet III Duke Brittany (age 55) died. Earl Richmond suspended. The succession of the Duchy of Brittany was disputed between Joan "Lame" Capet Countess Penthièvre (age 22) and [his half-brother] John Montfort IV Duke Brittany (age 46) leading to the War of the Breton Succession. His niece Joan succeeded Duchess Brittany 1221 Dreux. Charles "Saint" Chatillon Duke Brittany (age 22) by marriage Duke Brittany 1221 Dreux. His half brother John succeeded IV Duke Brittany 1221 Dreux. Joanna Dampierre Duchess Brittany (age 46) by marriage Duchess Brittany 1221 Dreux.

On 29th June 1344 [his former wife] Joan Savoy Duchess Brittany (age 34) died.