Proximity of blood

Proximity of blood, or closeness in degree of kinship, is one of the ways to determine hereditary succession based on genealogy. It was at loggerheads with primogeniture in numerous medieval succession disputes.

Feudal custom accorded quite a strong value to this claim.

Examples:

• In 1361, the Duchy of Burgundy would have gone to Charles II of Navarre according to primogeniture, but went to John II of France according to degree of kinship. Charles II of Navarre was grandson and heir to Margaret of Burgundy, second daughter of Duke Robert II of Burgundy. John II of France was son and heir to Joan of Burgundy, third daughter of Duke Robert II of Burgundy. John was first cousin of Philip's father, whereas Charles was son of a first cousin of Philip's father, i.e. a second cousin himself. Charles' mother Joan had died already 1349. John was thus one degree closer to Dukes of Burgundy than the primogeniture heir Charles.

• Earlier, Mary of Antioch claimed the throne of Jerusalem in 1269. She was the daughter of Prince Bohemond IV of Antioch and Tripoli (d. 1233) and his second wife Melisend of Cyprus (who died after 1249). Melisend was the youngest daughter of King Amalric I of Cyprus and his third wife Queen Isabella of Jerusalem. Since Mary was, at the time of the death of Conradin, the only living grandchild of Queen Isabella, she claimed the throne on basis of proximity in kinship to Conradin and to the Kings of Jerusalem. However, the Haute Cour of Kingdom awarded the succession to an heir of Melisend's elder sister, though he was a great-grandson of Isabella.

• Robert de Brus, 5th Lord of Annandale claimed the crown of Scotland in the 1290s using the argument of proximity of blood, while John Balliol made a rival claim based on primogeniture. Arbitration by Edward I of England awarded the throne to Balliol, but when Edward subsequently attempted to conquer Scotland, Robert de Brus' grandson and namesake took the throne as king and maintained Scottish independence; Bruce's success led to his acceptance as rightful king and Balliol's reign was disregarded as an usurpation; this established proximity of blood as a valid principle in the Scottish royal succession, although precedent and legislation also had a role.

Other examples:

• The Swedish Queen Ulrika Eleonora the Younger claimed the throne after her brother Charles XII's death in 1718 even though her older sister's son was alive.