Plebiscite and option.
§ 219. As the object of cession is sovereignty over the ceded territory, all such individuals domiciled thereon as are subjects of the ceding State become ipso facto by the cession subjects[424] of the acquiring State. The hardship involved in the fact that in all cases of cession the inhabitants of the territory lose their old citizenship and are handed over to a new Sovereign whether they like it or not, has created a movement in favour of the claim that no cession shall be valid until the inhabitants have by a plebiscite[425] given their consent to the cession. And several treaties[426] of cession concluded during the nineteenth century stipulate that the cession shall only be valid provided the inhabitants consent to it through a plebiscite. But it is doubtful whether the Law of Nations will ever make it a condition of every cession that it must be ratified by a plebiscite.[427] The necessities of international policy may now and then allow or even demand such a plebiscite, but in most cases they will not allow it.
[424] See Keith, "The Theory of State Succession, &c." (1907), pp. 42-45; Cogordan, "La Nationalité" (1890), pp. 317-400; Moore, III. § 379.
[425] See Stoerk, "Option und Plebiscite" (1879); Rivier, I. p. 204; Freudenthal, "Die Volksabstimmung bei Gebietsabtretungen und Eroberungen" (1891); Bonfils, No. 570; Despagnet, No. 391; Ullmann, § 97.
[426] See Rivier, I. p. 210, where all these treaties are enumerated.
[427] Although Grotius (II. c. VI. § 4) taught this to be necessary.
The hardship of the inhabitants being handed over to a new Sovereign against their will can be lessened by a stipulation in the treaty of cession binding the acquiring State to give the inhabitants of the ceded territory the option of retaining their old citizenship on making an express declaration. Many treaties of cession concluded during the second half of the nineteenth century contain this stipulation. But it must be emphasised that, failing a stipulation expressly forbidding it, the acquiring State may expel those inhabitants who have made use of the option and retained their old citizenship, since otherwise the whole population of the ceded territory might actually consist of aliens and endanger the safety of the acquiring State.
The option to emigrate within a certain period, which is frequently stipulated in favour of the inhabitants of ceded territory, is another means of averting the charge that inhabitants are handed over to a new Sovereign against their will. Thus article 2 of the Peace Treaty of Frankfort, 1871, which ended the Franco-German war, stipulated that the French inhabitants of the ceded territory of Alsace and Lorraine should up to October 1, 1872, enjoy the privilege of transferring their domicile from the ceded territory to French soil.[428]
[428] The important question whether subjects of the ceding States who are born on the ceded territory but have their domicile abroad become ipso facto by the cession subjects of the acquiring State, must, I think, be answered in the negative, unless special treaty arrangements stipulate the contrary. Therefore, Frenchmen born in Alsace but domiciled at the time of the cession in Great Britain, would not have lost their French citizenship through the cession to Germany but for article 1, part 2, of the additional treaty of Dec. 11, 1871, to the Peace Treaty of Frankfort. (Martens, N.R.G. XX. p. 847.) See Bonfils, No. 427, and Cogordan, "La Nationalité, &c." (1890), p. 361.