NATURALIZATION, the term given in law to the acquisition by an alien of the national character or citizenship of a certain state, always with the consent of that state and of himself, but not necessarily with the consent of the state to which he previously belonged, which may refuse to its subjects the right of renouncing its nationality, called " expatriation," or may allow the right only on conditions which have not been fulfilled in the particular case. Hence although nationality in strict theory is always single, as liege homage was and allegiance in its proper sense is, it often happens that two states claim the same person as their national or subject. This conflict arises not only from naturalization having, been granted without the corresponding expatriation having been permitted, but also from the fact that birth on the soil was the leading determinant of nationality by feudal law, and still is so by the laws of England and the United States (jus soli), while the nationality of the father is its leading determinant in those countries which have accepted Roman principles of jurisprudence (jus sanguinis). The conflict is usually solved for practical purposes by an understanding which is approximately general, namely that, in cases not provided for by treaty, no state shall protect those whom it claims as its nationals while residing in the territory of another state which claims them as its own nationals by any title, whether jus soli, jus sanguinis, naturalization, or the refusal to allow expatriation. On this footing the British foreign office, while it grants passports for travel to naturalized persons, will extend no protection to them against a claim of their former country, if they return to it, to exact military service due to it. The United States, asserting that expatriation is an inalienable right of man, maintains that, to lose his right to American protection, the emigrant who has been naturalized in the United States must have done that for which he might have been tried and punished at the moment of his departure; it claims to protect him against the exaction of what at that moment was merely a future liability 1 Cf. Spencer, First Principles (1867), p. 398.
2 Cf. Prolegomena, 60.
to military service, and this doctrine has been practically accepted by France in her dealings with America. Germany also accepted it by the treaty of 1868 between the United States and the North German Confederation, now in force for the German empire, subject to provisions that the emigrant's fixing his domicile in the old country shall be deemed a renunciation of his naturalization in the new, and that his living in the old country for more than two years may be deemed to imply the absence of an intention to return to the new. Between the United States and Great Britain the convention of the 13th of May 1870 provides that naturalization in either is to be valid for all purposes immediately on its completion, but that if the resident shall renew his residence in his old country he may be readmitted to his old nationality, on his application and on such conditions as the readmitting government may impose.
The Naturalization Act 1870, which now governs the matter for England, does not say that the person naturalized becomes thereby a British subject, to which, if it had been said, a proviso might have been added saving the above-mentioned policy of the foreign office as to not protecting him in his old country, although even without such a proviso the foreign office would have been free to follow that policy. The act in question (s. 7) gives him the rights and imposes on him the duties of a naturalborn British subject in the United Kingdom, and provides that, when within the limits of his old country, he shall not be deemed a British subject unless he has ceased to be a subject of that country, by its laws or in pursuance of a treaty. On this wording it has been maintained that British naturalization is not really naturalization at all; but leaves the naturalized person as he was with the addition of a certain quality within the United Kingdom; and on that ground it has been considered in France that a Frenchman, obtaining naturalization in England, does not fall within the French law (Code Civil, Art. 17) which pronounces the expatriation of citizens who cause themselves to be naturalized abroad. This is the Bourgoise Case, 41 Ch. D. 310, in which, when it came before the English courts, Mr Justice Kay inclined to the same view, but the court of appeal avoided giving an opinion on the point. Professor Dicey leans to the same view (5 Law Quarterly Review, 438); but Sir Thomas Barclay (4 L.Q.R. 226), Sir Malcolm Mcllwraith (6 L.Q.R. 379), and Professor Westlake (International Law Peace, 2nd ed. p. 234; Private International Law, 4th ed. p. 356) adopt the view that the Naturalization Act 1870 makes the naturalized person a full British subject, only to be treated in his old country in accordance with the international principles recognized by the British executive. And the foreign office, by granting passports to naturalized persons, acts on the same view. The point is important with reference to the question whether the naturalization of the father in the United Kingdom confers the character of British subjects on his children afterwards born abroad. (See ALIEN.)
An analogous question arises on the provision in the Naturalization Act 1870, sec. 16, that the legislature of any British possession may make laws " for imparting to any person the privileges of naturalization, to be enjoyed by such person within the limits ' of such possession." This, in accordance with the wider view of the effect of naturalization in the United Kingdom, may mean that naturalization in pursuance of a colonial law confers the full character of a British subject, only without removing disabilities, such as that to hold land, under which the naturalized person may have lain as an alien in any other British possession. On that footing the foreign office grants passports to the holders of colonial certificates of naturalization, and protects them in all foreign countries but that of their origin; and the Merchant Shipping Act 1894, sec. i, allows persons naturalized in British possessions to be owners of British ships. On the other hand, those who maintain the narrower view of the effect of naturalization in the United Kingdom naturally hold that colonial naturalization has no effect at all outside the British possession in which it is granted.
Naturalization in India is regulated by the Indian Naturalization Act, No. 30 of 1852, under which it may be granted to subjects of the several princes and states in India as well as to those who are entirely aliens to the British empire. The former, however, are treated for several purposes as British subjects even without being so naturalized.
In most countries a lengthened sojourn is a condition precedent to naturalization. In Belgium, the United Kingdom, North America and Russia the period of such sojourn is fixed at five years, in France, Greece and Sweden at three, in the Argentine Republic two, while in Portugal a residence of one year is sufficient. In Germany, Austria and Italy no period of residence is prescribed, while in Austria a ten years' residence confers per se the rights of citizenship. In the United States an alien desiring to be naturalized must declare on oath his intention to become a citizen of the United States; two years afterwards must declare on oath his intention to support the constitution of the United States and renounce allegiance to every foreign power, including that of which he was before a subject; must prove residence in the United States for five years, and in the state where his application is made for one year, as a good citizen; and must renounce any title of nobility. In France an alien desiring naturalization, if he has not resided continuously in the country for ten years, must obtain permission to establish his domicile in France; three years after (in special cases one year) he is entitled to apply for naturalization, which involves the renunciation of any existing allegiance.
See further, ALLEGIANCE, INTERNATIONAL LAW (Private); also Bar, Private International Law (Gillespie's translation) ; Hansard, Law relating to Aliens; Cutler, Law of Naturalization; Cockburn, Nationality; Cogordan, Nationalite; Heffter, Europdisches Volkerrecht; Hall, Foreign Jurisdiction of the British Crown; Westlake, International Law Peace, and Private International Law (4th ed.).