Arthur was born in 1187, the son of Duchess
Constance and Duke
Geoffrey II of Brittany. Geoffrey died before Arthur was born. As an infant, Arthur was thought by some to be second in line to the succession of his paternal grandfather, King
Henry II of England, after his uncle
Richard. Henry II however would not name official terms of succession, not even officially naming Richard as his heir until he was close to death.
Primogeniture was not yet established, nor the pathway that the crown should take. King Henry died when Arthur was 2 years old, and Richard I became the new king in his place. While Richard was away on the
Third Crusade, Arthur's mother Constance sought to make the
Duchy of Brittany more independent. On 11 November 1190, Arthur was named as Richard's
heir presumptive and was betrothed to a daughter of King
Tancred of Sicily as part of their treaty. However,
Emperor Henry VI conquered the
Kingdom of Sicily in 1194, so the betrothal of Arthur came to nothing. A marriage plan, originally aiming to establish an alliance between King Richard and King
Philip II of France to marry Arthur's elder sister
Eleanor to Philip's son
Louis also failed. In 1196, Constance had the young Arthur proclaimed Duke of Brittany and her co-ruler as a child of nine years. The same year, Richard summoned Arthur, as well as Arthur's mother, Constance, to Normandy, but
Ranulf de Blondeville, 6th Earl of Chester, stepfather of Arthur, abducted Constance. It is believed that this was completed under the agreement, and even prompting, of Richard to bring Constance and Arthur under his control, as it is extremely unlikely that Ranulf would have made such a move against Richard's sister-in-law and nephew without such permission. Constance was captured, but Arthur was spirited away to the Court of Philip II of France, to be brought up with Louis. .
Chroniques de St Denis,
British Library. When Richard died on 6 April 1199, on his deathbed he proclaimed his brother
John as his heir, fearing Arthur was too young to look after the throne, but also under the influence of Philip II. Arthur was only twelve years old at the time. John immediately claimed the throne of England, but much of the Norman nobility were resentful, or concerned, at recognising him as their overlord based upon previous experiences and issues with him, such as when Richard was away on Crusade and John gave away Plantagenet lands to Philip II in an attempt to take control while Richard was absent. They preferred Arthur, who declared himself
vassal of Philip, but also was the Duke of Brittany. Philip recognised Arthur's right to
Anjou,
Maine, and
Poitou. Upon Richard's death Arthur led a force to Anjou and Maine. From 18 April, he styled himself as Duke of Brittany, Count of Anjou and Earl of Richmond. On 18 September, John persuaded the
seneschal of Anjou,
William des Roches, to defect, claiming Arthur would be a
Capetian puppet. Four days later William took Arthur and Constance prisoners to
Le Mans. Viscount Aimery, the seneschal appointed by John, took Arthur and Constance and fled the court to
Angers, and later the court of Philip II. ==Treaty of Le Goulet==