24) These corollaries are components of the concept of ligeance described in Calvin's Case.
The rationale for territorial birthright citizenship has its basis in the feudal system of early England, where ligeance to a king or lord was a component of the feudal relationship.
According to the defendants, Calvin was not a subject of King James' realm of England because Calvin was not under the ligeance of the king's body politic in England.
Calvin's Case stands for the proposition that, with certain limited exceptions founded on a ligeance requirement, a child born within a sovereign's territory is a sovereign's subject, or, in modern parlance, a citizen.
While the child may be born in the United States, the child, under the opponents' theory, is not subject to the jurisdiction because his parent is not under the ligeance, or consent in modern parlance, of the U.
rule of territorial birthright citizenship is fortified by Calvin's Case, which expounded the territorial nature of ligeance and manifests consent broadly,(166) limited only by the common law exceptions for children born of diplomats and children born of hostile occupying forces.