Calvin”s Case

What does Calvin”s Case mean in American Law?

The definition of Calvin”s Case in the law of the United States, as defined by the lexicographer Arthur Leff in his legal dictionary is:

A 1608 case in which it was held that persons born in Scotland after the 1603 personal merger of the Crowns of England and Scotland in the person of James I were not aliens (and thus unable to inherit English land). In effect, the decision established that the merger of England and Scotland had also taken place at a political level, and not just as a matter [of] late medieval dynastic law.