'''''Calvin's Case'' (1608), 77 ER 377, (1608) Co Rep 1a, also known as the ''Case of the Postnati''''', was a 1608 English legal decision establishing that a child born in Scotland, after the Union of the Crowns under King James VI and I in 1603, was considered under the common law to be an English subject and entitled to the benefits of English law. ''Calvin's Case'' was eventually adopted by courts in the United States, and the case played an important role in shaping the American rule of birthright citizenship via ''jus soli'' ("law of the soil", or citizenship by virtue of birth within the territory of a sovereign state).
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