Proximity in blood

Proximity of blood, or proximity by degree of kinship, is one of the ways to determine hereditary succession based on genealogy. In effect, the application of this rule is a refusal to recognize the right of representation, a component of primogeniture.

In some feudal entities, proximity of blood was a generally accepted principle. For example, it is called the "ancient custom" (French: ancien coutume) in the Duchy of Burgundy, where a grandson could not take precedence over a son, and it was not even clear whether the ruler's grandson could claim precedence over the ruler's brother.

Proximity of blood and primogeniture were at loggerheads in numerous medieval succession disputes.

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