If I understand correctly (and I may not), one was not a subject of "England" per se, but a subject of the "Crown" or the sovereign King of England as the divine ruler from God.
Since we don't have Kings in the United States, the concept of "subject" does not transfer easily. The closest thing to define "natural born," then, becomes born to citizens of the country, since the citizenry are sovereign.
This is why America was called the "great experiment," and why we have the phrase "American exceptionalism." It is because, until the Declaration and Constitution, all countries were formed by either conquest or by subjection to religious monarchies as laid out in Thomas Paine's The Rights Of Man. America was created as a Constitutional Republic, where the rule of law defined the nation, and that nation's natural citizenry were its descendents (or Posterity, as it's referred to in the Constitution).
From The Rights of Man, Applying Principle to Practice, Chapter 4 — Of Constitutions, Part 2 of 2:
If there is any government where prerogatives might with apparent safety be entrusted to any individual, it is in the federal government of America. The president of the United States of America is elected only for four years. He is not only responsible in the general sense of the word, but a particular mode is laid down in the constitution for trying him. He cannot be elected under thirty-five years of age; and he must be a native of the country.-PJIn a comparison of these cases with the Government of England, the difference when applied to the latter amounts to an absurdity. In England the person who exercises prerogative is often a foreigner; always half a foreigner, and always married to a foreigner. He is never in full natural or political connection with the country, is not responsible for anything, and becomes of age at eighteen years; yet such a person is permitted to form foreign alliances, without even the knowledge of the nation, and to make war and peace without its consent.
But this is not all. Though such a person cannot dispose of the government in the manner of a testator, he dictates the marriage connections, which, in effect, accomplish a great part of the same end. He cannot directly bequeath half the government to Prussia, but he can form a marriage partnership that will produce almost the same thing. Under such circumstances, it is happy for England that she is not situated on the Continent, or she might, like Holland, fall under the dictatorship of Prussia. Holland, by marriage, is as effectually governed by Prussia, as if the old tyranny of bequeathing the government had been the means.
The presidency in America (or, as it is sometimes called, the executive) is the only office from which a foreigner is excluded, and in England it is the only one to which he is admitted. A foreigner cannot be a member of Parliament, but he may be what is called a king. If there is any reason for excluding foreigners, it ought to be from those offices where mischief can most be acted, and where, by uniting every bias of interest and attachment, the trust is best secured. But as nations proceed in the great business of forming constitutions, they will examine with more precision into the nature and business of that department which is called the executive. What the legislative and judicial departments are every one can see; but with respect to what, in Europe, is called the executive, as distinct from those two, it is either a political superfluity or a chaos of unknown things.
Yes, Paine did use the term "native of the country." Does this mean "native born" instead of "natural born?" We have to look at the following statements to answer that question.
Paine refers to Engish examples in order to define this. Paine cites "foreigner" and "half a foreigner" as the oppposite to "full natural" connection to the country. So, what is "half a foreigner?"
It seems to me that "half a foreigner" is a person with one parent who is a citizen and one parent who is not. This person does not have have a "full natural... connection with the country."
I'd also say that Paine was a widely read author of the time of the Declaration and the Constitution, and so his writings do reflect the common understandings of the language at the time. I'm sure that the Founders and the Framers shared this understanding of the language.
-PJ
I guess it takes one to know one! Thanks