The Law of Nations or the Principles of Natural Law (1758)

Emmerich de Vattel

Of the Right of Postliminium

§ 204. Definition of the right of postliminium1
THE right of postliminium is that in virtue of which persons and things taken by the enemy are restored to their former state, on coming again into the power of the nation to which they belonged.2

§ 205. Foundation of this right.
The sovereign is bound to protect the persons and property of his subjects, and to defend them against the enemy. When, therefore, a subject, or any part of his property, has fallen into the enemy’s possession, should any fortunate event bring them again into the sovereign’s power, it is undoubtedly his duty to restore them to their former condition, — to re-establish the persons in all their rights and obligations, to give back the effects to the owners, — in a word, to replace every thing on the same footing on which it stood previous to the enemy’s capture.

The justice or injustice of the war makes no difference in this case, — not only because, according to the voluntary law of nations, the war, as to its effects, is reputed just on both sides, but likewise because war, whether just or not, is a national concern; and, if the subjects who fight or suffer in the national cause, should, after they have, either in their persons or their property, fallen into the enemy’s power, be, by some fortunate incident, restored to the hands of their own people, there is no reason why they should not be restored to their former condition. It is the same as if they had never been taken. If the war be just on the part of their nation, they were unjustly captured by the enemy; and thus nothing is more natural than to restore them as soon as it becomes possible. If the war be unjust, they are under no greater obligation to suffer in atonement for its injustice than the rest of the nation. Fortune brings down the evil on their heads when they are taken: she delivers them from it when they escape. Here, again, it is the same as if they never had been captured. Neither their own sovereign, nor the enemy, has any particular right over them. The enemy has lost by one accident what he had gained by another.

§ 206. How it takes effect.
Persons return, and things are recovered, by the right of postliminium, when, after having been taken by the enemy, they come again into the power of their own nation (§ 204). This right, therefore, takes effect as soon as such persons or things captured by the enemy fall into the hands of soldiers belonging to their own nation, or are brought back to the army, the camp, the territories of their sovereign, or the places under his command.

§ 207. Whether it takes effect among the allies.
Those who unite with us to carry on a war are joint parties with us: we are engaged in a common cause; our right is one and the same; and they are considered as making but one body with us. Therefore, when persons or things captured by the enemy are retaken by our allies or auxiliaries, or in any other manner fall into their hands, this, so far as relates to the effect of the right, is precisely the same thing as if they were come again into our own power; since, in the cause in which we are jointly embarked, our power and that of our allies is but one and the same. The right of postliminium therefore takes effect among those who carry on the war in conjunction with us; and the persons and things recovered by them from the enemy are to be restored to their former condition.3

But, does this right take place in the territories of our allies? Here a distinction arises. If those allies make a common cause with us, — if they are associates in the war, — we are necessarily entitled to the right of postliminium in their territories as well as in our own: for, their state is united with ours, and together with it, continues but one party in the war we carry on. But if, as in our times is frequently the practice, an ally only gives us a stated succor stipulated by treaty, and does not himself come to a rupture with our enemy, between whose state and his own, in their immediate relations, peace continues to be observed, — in this case, only the auxiliaries whom he sends to our assistance are partakers and associates in the war; and his dominions remain in a state of neutrality.

§ 208. Of no validity in neutral nations.
Now, the right of postliminium does not take effect in neutral countries: for, when a nation chooses to remain neuter in a war, she is bound to consider it as equally just on both sides, so far as relates to its effects, — and, consequently, to look upon every capture made by either party as a lawful acquisition. To allow one of the parties, in prejudice to the other, to enjoy in her dominions the right of claiming things taken by the latter, or the right of postliminium, would be declaring in favor of the former, and departing from the line of neutrality.

§ 209. What things are recoverable by this right.4
Naturally, every kind of property might be recovered by the right of postliminium; and there is no intrinsic reason why movables should be excepted in this case, provided they can be certainly recognized and identified. Accordingly, the ancients, on recovering such things from the enemy, frequently restored them to their former owners.5 But the difficulty of recognising things of this nature, and the endless disputes which would arise from the prosecution of the owners’ claims to them, have been deemed motives of sufficient weight for the general establishment of a contrary practice. To these considerations we may add, that, from the little hope entertained of recovering effects taken by the enemy and once carried to a place of safety, a reasonable presumption arises that the former owners have relinquished their property. It is therefore with reason that movables or booty are excepted from the right of postliminium, unless retaken from the enemy immediately after his capture of them; in which case, the proprietor neither finds a difficulty in recognising his effects, nor is presumed to have relinquished them. And, as the custom has once been admitted, and is now well established, there would be an injustice in violating it (Prelim, § 26). Among the Romans, indeed, slaves were not treated like other movable property: they, by the right of postliminium, were restored to their masters, even when the rest of the booty was detained. The reason of this is evident: for, as it was at all times easy to recognize a slave, and ascertain to whom he belonged, the owner, still entertaining hopes of recovering him, was not supposed to have relinquished his right.

§ 210. Of those persons who cannot return by the right of postliminium.6.
Prisoners of war, who have given their parole, — territories and towns which have submitted to the enemy, and have sworn or promised allegiance to him, — cannot of themselves return to their former condition by the right of postliminium: for, faith is to be kept even with enemies (§ 174).

§ 211. They enjoy this right when retaken.
But if the sovereign retakes those towns, countries, or prisoners, who had surrendered to the enemy, he recovers all his former rights over them, and is bound to re-establish them in their pristine condition (§ 205). In this case, they enjoy the right of postliminium without any breach of their word, any violation of their plighted faith. The enemy loses by the chance of war a right which the chance of war had before given him. But, concerning prisoners of war, a distinction is to be made. If they were entirely free on their parole, the single circumstance of their coming again into the power of their own nation does not release them, — since, even if they had returned home, they would still have continued prisoners. The consent of the enemy who had captured them, or his total subjugation, can alone discharge them. But, if they have only promised not to effect their escape, — a promise which prisoners frequently make in order to avoid the inconveniences of a jail, — the only obligation incumbent on them is, that they shall not, of themselves, quit the enemy’s country, or the place assigned for their residence. And if the troops of their party should gain possession of the place where they reside, the consequence is, that, by the right of war, they recover their liberty, are restored to their own nation, and reinstated in their former condition.7

§ 212. Whether this right extends to their property alienated by the enemy.
When a town, reduced by the enemy’s arms, is retaken by those of her own sovereign, she is, as we have above seen, restored to her former condition, and reinstated in the possession of all her rights. It is asked whether she thus recovers such part of her property as had been alienated by the enemy while he kept her in subjection. In the first place, we are to make a distinction between movable property not recoverable by the right of postliminium (§ 202), and immovables. The former belongs to the enemy who gets it into his hands, and he may irrecoverably alienate it. As to immovables, let it be remembered that the acquisition of a town taken in war is not fully consummated till confirmed by a treaty of peace, or by the entire submission or destruction of the state to which it belonged (§ 197). Till then, the sovereign of that town has hopes of retaking it, or of recovering it by a peace. And from the moment it returns into his power, he restores it to all its rights (§ 205), and consequently it recovers all its possessions, as far as in their nature they are recoverable. It therefore resumes its immovable possessions from the hands of those persons who have been so prematurely forward to purchase them. In buying them of one who had not an absolute right to dispose of them, the purchasers made a hazardous bargain; and if they prove losers by the transaction, it is a consequence to which they deliberately exposed themselves. But if that town had been ceded to the enemy by a treaty of peace, or was completely fallen into his power by the submission of the whole state, she has no longer any claim to the right of postliminium; and the alienation of any of her possessions by the conqueror is valid and irreversible; nor can she lay claim to them, or, in me sequel, some fortunate revolution should liberate her from the yoke of the conqueror. When Alexander made a present to the Thessalians of the sum due from them to the Thebans (see § 77), he was so absolutely master of the republic of Thebes, that he destroyed the city and sold the inhabitants.

The same decisions hold good with regard to the immovable property of individuals, prisoners or not, which has been alienated by the enemy while he was master of the country. Grotius proposes the question with respect to immovable property possessed in a neutral country by a prisoner of war.8 But, according to the principles we have laid down, this question is groundless: for, the sovereign who makes a prisoner in war, has no other right over him than that of detaining his person until the conclusion of the war, or until he be ransomed (§§ 148, etc.); but he acquires no right to the prisoner’s property, unless he can seize on it. It is impossible to produce any natural reason why the captor should have a right to dispose of his prisoner’s property, unless the prisoner has it about him.

§ 213. Whether a nation that has been entirely subdued can enjoy the right of postliminium.
When a nation, a people, a state, has been entirely subdued, it is asked whether a revolution can entitle them to the right of postliminium. In order justly to answer this question, there must again be a distinction of cases, If that conquered state has not yet acquiesced in her new subjection, has not voluntarily submitted, and has only ceased to resist from inability, — if her victor has not laid aside the sword of conquest and taken up the scepter of peace and equity, — such a people are not really subdued: they are only defeated and oppressed; and, on being delivered by the arms of an ally, they doubtless return to their former situation (§ 207). Their ally cannot become their conqueror; he is their deliverer; and all the obligation of the party delivered is to reward him. If the subsequent conqueror, not being an ally to the state of which we speak, intends to keep it under his own jurisdiction as the reward of his victory, he puts himself in the place of the former conqueror, and becomes the enemy of the state which the other had oppressed: that state may lawfully resist him, and avail herself of a favorable opportunity to recover her liberty. If she had been unjustly oppressed, he who rescues her from the yoke of the oppressor ought generously to reinstate her in the possession of all her rights (§ 203).

The question changes with regard to a state which has voluntarily submitted to the conqueror. If the people, no longer treated as enemies, but as actual subjects, have submitted to a lawful government, they are thenceforward dependent on a new sovereign; or, being incorporated with the victorious nation, they become a part of it, and share its fate. Their former state is absolutely destroyed; all its relations, all its alliances are extinguished (Book II. § 203). Whoever, then, the new conqueror may be, that afterwards subdues the state to which these people are united, they share the destiny of that state, as a part shares the fate of the whole. This has been the practice of nations in all ages, — I say, even of just and equitable nations, — especially with regard to an ancient conquest. The most moderate conqueror confines his generosity in this particular to the restoration of the liberties of a people who have been but recently subdued, and whom he does not consider as perfectly incorporated, or well cemented by inclination, with the state which he has conquered.

If the people in question shake off the yoke and recover their liberty by their own exertions, they regain all their rights; they return to their former situation; and foreign nations have no right to determine whether they have shaken off the yoke of lawful authority, or burst the chains of slavery. Thus, the kingdom of Portugal, — which had been seized on by Philip II. king of Spain, under pretense of an hereditary right, but in reality by force and the terror of his arms, — re-established the independency of her crown, and recovered her former rights, when she drove out the Spaniards, and placed the duke of Braganza on the throne.

§ 214. Right of postliminium for what is restored at the peace.
Provinces, town, and lands, which the enemy restores by the treaty of peace, are certainly entitled to the right of postliminium: for the sovereign, in whatever manner he recovers them, is bound to restore them to their former condition, as soon as he regains possession of them (§ 205). The enemy, in giving back a town at the peace, renounces the right he had acquired by arms. It is just the same as if he had never taken it; and the transaction furnishes no reason which can justify the sovereign in refusing to reinstate such town in the possession of all her rights, and restore her to her former condition.

§ 215. and for things ceded to the enemy.
But whatever is ceded to the enemy by a treaty of peace, is truly and completely alienated. It has no longer any claim to the right of postliminium, unless the treaty of peace be broken and canceled.

§ 216. The right of postliminium does not exist after a peace.
And as things not mentioned in the treaty of peace remain in the condition in which they happen to be at the time when the treaty is concluded, and are, on both sides, tacitly ceded to the present possessor, it may be said, in general, that the right of postliminium no longer exists after the conclusion of the peace. That right entirely relates to the states of war.

§ 217. Why always in force for prisoners.
Nevertheless, and for this very reason, there is an exception to be made here in favor of prisoners of war. Their sovereign is bound to release them at the peace (§ 154). But, if he cannot accomplish this, — if the fate of war compels him to accept of hard and unjust conditions, — the enemy, who ought to set the prisoners at liberty when the war is terminated, and he has no longer any thing to fear from them (§§ 150, 153), continues the state of war with respect to them, if he still detains them in captivity, and especially if he reduces them to slavery (§ 152). They have therefore a right to effect their escape from him, if they have an opportunity, and to return to their own country, equally as in war time; since, with regard to them, the war still continues. And in that case, the sovereign, from his obligation to protect them, is bound to restore them to their former condition (§ 205).

§ 218. They are free even by escaping into a neutral country.
Further, those prisoners who are, without any lawful reason, detained after the conclusion of peace, become immediately free, when, once escaped from captivity, they have even reached a neutral country: for, enemies are not to be pursued and seized on neutral ground (§ 132); and whoever detains an innocent prisoner after the peace, continues to be his enemy. This rule should and actually does obtain among nations who do not admit and authorize the practice of enslaving prisoners of war.

§ 219. How the rights and obligations of prisoners subsist.
It is sufficiently evident from the premises, that prisoners are to be considered as citizens who may one day return to their country: and, when they do return, it is the duty of the sovereign to re-establish them in their former condition. Hence it clearly follows, that the rights of every one of those prisoners, together with his obligations (or the rights of others over him), still subsist undiminished, — only the exertion of them is, for the most part, suspended during the time of his captivity.

§ 220. Testament of a prisoner of war.
The prisoner of war therefore retains a right to dispose of his property, particularly in case of death: and, as there is nothing in the state of captivity which can in this latter respect deprive him of the exercise of his right, the testament of a prisoner of war ought to be valid in his own country, unless rendered void by some inherent defect.

§ 221. Marriage.
With nations which have established the indissolubility of the marriage ties, or have ordained that they should continue for life unless dissolved by the judgment of a court, those ties still subsist, notwithstanding the captivity of one of the parties, who, on his return home, is, by postliminium, again entitled to all his matrimonial rights.

§ 222. Regulations respecting postliminium, established by treaty or custom.
We do not here enter into a detail of what the civil laws of particular nations have ordained with respect to the right of postliminium: we content ourselves with observing that such local regulations are obligatory on the subjects of the state alone, and do not affect foreigners. Neither do we here examine what has been settled on the head by treaties: those particular compacts establish merely a conventional right, which relates only to the contracting parties. Customs confirmed by long and constant use are obligatory on those nations who have given a tacit consent to them; and they are to be respected, when not contrary to the law of nature: but those which involve an infringement of that sacred law are faulty and invalid; and, instead of conforming to such customs, every nation is bound to use her endeavors to effect their abolition. Among the Romans the right of postliminium, was in force, even in times of profound peace, with respect to nations with which Rome had neither connections of friendship, lights of hospitality, nor alliance.9 This was because those nations were, as we have already observed, considered in some measure as enemies. The prevalence of milder manners has almost everywhere abolished that remnant of barbarism.


     1.    See, in general, 1 Chitty’s Commercial Law, 430 to 435; Id. Index, tit. Postliminium. — C.
     2.    See ante, § 196, chap. 13, note 1, as to movables and ships. — C.
     3.    As to the general rule in the absence of treaty, see Santa Cruz, 1 Rob. Rep. 49; ante, chap. 13, note 1. But, in general, the precise rule is fixed by treaty between allies. Id ibid — C.
     4.    As to movables and ships, ante, 384, n. — C.
     5.    See several instances in Grotius, book iii, ch. xvi § 2.
     6.    In general, as regards countries of persons taken by a belligerent state, who were not the subjects of that state during any preceding part of the same war, a different rule prevails than that laid down by Vattel, sect, 211; for, the law of postliminium implies that the party claiming it returns to his previous character. And he who, during the whole war, has been the subject of the enemy alone, must be considered, when he falls into the hands of the rival state, not as returning to a previous character, but as acquiring a character absolutely new. Upon this principle was decided an important question in the case of Boedes Lust, 5 Rob. Rep. 233; and on the same principle it was established that, if a neutral have but just set his foot on the colony of an enemy for a few hours before its capture; but if it be proved that he went there for the purpose of settling, then his property will be subject to condemnation, as if he were a native enemy. And see the Dianna. 5 Rob. Rep. 60. — C.
     7.    Ibid.
     8.    Lib. iii. cap. ix. § vi.
     9.    Digest, lib. xlix. de Capt. et Postlim. leg. v. § ii.