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Arthur I,1187–1203?, duke of Brittany (1196–1203?), son of Geoffrey, fourth son of Henry II of England and Constance, heiress of Brittany. Arthur, a posthumous child, was proclaimed duke in 1196, and an invasion by his uncle King Richard I of England was repulsed with French aid. Subsequently, Arthur was brought up at the court of King Philip II of France. On Richard's death (1199), Arthur's claim to the English crown was passed over in favor of his uncle JohnJohn,
1167–1216, king of England (1199–1216), son of Henry II and Eleanor of Aquitaine. Early Life
The king's youngest son, John was left out of Henry's original division of territory among his sons and was nicknamed John Lackland.
..... Click the link for more information. , youngest son of Henry II. Arthur allied himself with Philip II, who invested him with all of Richard's fiefs in France. The nobles of Anjou, Maine, and Touraine recognized Arthur as their ruler, but the young duke was captured (1202) by John while attempting to subdue Poitou. He was imprisoned in Rouen; his fate is uncertain, although John was suspected of murdering him in 1203. His story is told in Shakespeare's King John. Arthur's sister and heir married Pierre Mauclerc, who later became duke of Brittany as Peter IPeter I
(Pierre Mauclerc), d. 1250, duke or count of Brittany (1213–37). The son of Robert II, count of Dreux, he married Alix, half-sister and heiress of Arthur I duke of Brittany.
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