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

Emmerich de Vattel

Treaties of Peace

§ 9. Definition of a treaty of peace.1
WHEN the belligerent powers have agreed to lay down their arms, the agreement or contract in which they stipulate the conditions of peace, and regulate the manner in which it is to be restored and supported, is called the treaty of peace.

§ 10. By whom it may be concluded.
The same power who has the right of making war, of determining on it, of declaring it, and of directing its operations, has naturally that likewise of making and concluding the treaty of peace.2 These two powers are connected together, and the latter naturally follows from the former. If the ruler of the state is empowered to judge of the causes and reasons for which war is to be undertaken, — of the time and circumstances proper for commencing it, — of the manner in which it is to be supported and carried on, — it is therefore his province also to set bounds to its progress, to point out the time when it shall be discontinued, and to conclude a peace. But this power does not necessarily include that of granting or accepting whatever conditions he pleases, with a view to peace. Though the state has intrusted to the prudence of her ruler the general care of determining on war and peace, yet she may have limited his power in many particulars by the fundamental laws. Thus, Francis the First, king of France, had the absolute disposal of war and peace: and yet the assembly of Cognac declared that he had no authority to alienate any part of the kingdom by a treaty of peace. (See Book I. § 265.)

A nation that has the free disposal of her domestic affairs, and the form of her government, may intrust a single person, or an assembly, with the power of making peace, although she has not given them that of making war. Of this we have an instance in Sweden, where, since the death of Charles XII., the king cannot declare war without the consent of the states assembled in diet; but he may make peace in conjunction with the senate. It is less dangerous for a nation to intrust her rulers with this latter power, than with the former. She may reasonably expect that they will not make peace till it suits with the interest of the state. But their passions, their own interest, their private views, too often influence their resolutions where there is question of undertaking a war. Besides, it must be a very dangerous peace, indeed, that is not preferable to war, whereas, on the other hand, to exchange peace for war is always very hazardous.

When a prince, who is possessed only of limited authority, has a power to make peace, as he cannot of himself grant whatever conditions he pleases, it is incumbent on those who wish to treat with him on sure grounds, to require that the treaty of peace be ratified by the nation, or by those who are empowered to perform the stipulations contained in it. If, for instance, any potentate, in negotiating a treaty of peace with Sweden, requires a defensive alliance or guarantee as the condition, this stipulation will not be valid, unless approved and accepted by the diet, who alone have the power of carrying it into effect. The kings of England are authorized to conclude treaties of peace and alliance; but they cannot, by those treaties, alienate any of the possessions of the crown without the consent of parliament. Neither can they, without the concurrence of that body, raise any money in the kingdom; wherefore, whenever they conclude any subsidiary treaty, it is their constant rule to lay it before the parliament, in order that they may be certain of the concurrence of that assembly to enable them to make good their engagements. When the emperor Charles V. required of Francis the First, his prisoner, such conditions as that king could not grant without consent of the nation, he should have detained him till the states-general of France had ratified the treaty of Madrid, and Burgundy had acquiesced in it: thus he would not have lost the fruits of his victory by an oversight which appears very surprising in a prince of his abilities.

§ 11. Alienations made by a treaty of peace.
We shall not repeat here what we have said on a former occasion concerning the alienation of a part of the state (Book I. §§ 263, etc.) or of the whole state. (Ibid. §§ 68, etc.) We shall therefore content ourselves with observing, that, in case of a pressing necessity, such as is produced by the events of an unfortunate war, the alienations made by the prince, in order to save the remainder of the state, are considered as approved and ratified by the mere silence of the nation, when she has not, in the form of her government, retained some easy and ordinary method of giving her express consent, and has lodged an absolute power in the prince’s hands. The states-general are abolished in France by disuse, and by the tacit consent of the nation. Whenever, therefore, that kingdom is reduced to any calamitous exigency, it belongs to the king alone to determine by what sacrifices he may purchase peace: and his enemies will treat with him on a sure footing. It would be a vain plea on the part of the people, to say that it was only through fear they acquiesced in the abolition of the states-general. The fact is, that they did acquiesce, and thereby suffered the king to acquire all the powers necessary for contracting with foreign states in the name of the nation. In every state there must necessarily be some power with which other nations may treat on secure grounds. A certain historian3 says, that, “by the fundamental laws, the kings of France cannot, to the prejudice of their successors, renounce any of their rights, by any treaty, whether voluntary or compulsory.” The fundamental laws may indeed withhold from the king the power of alienating, without the nation’s consent, what belongs to the state; but they cannot invalidate an alienation or renunciation made with that consent.4

And if the nation has permitted matters to proceed to such lengths that she now has no longer any means of expressly declaring her consent, her silence alone, on such occasions, is in reality a tacit consent. Otherwise there would be no possibility of treating on sure grounds with such a state; and her pretending thus beforehand to invalidate all future treaties would be an infringement of the law of nations, which ordains that all states should retain the means of treating with each other (Book I, § 262), and should observe their treaties. (Book II. §§ 163, 269, etc.)

It is to be observed, however, that in our examination whether the consent of the nation be requisite for alienating any part of the state, we mean such parts as are still in the nation’s possession, and not those which have fallen into the enemy’s hands during the course of the war: for, as these latter are no longer possessed by the nation, it is the sovereign alone, if invested with the full and absolute administration of the government, and with the power of making war and peace, — it is he alone, I say, who is to judge whether it be expedient to relinquish those parts of the state, or to continue the war for the recovery of them. And even though it should be pretended that he cannot by his own single authority make any valid alienation of them, — he has, nevertheless, according to our supposition, that is, if invested with full and absolute power, — he has, I say, a right to promise that the nation shall never again take up arms for the recovery of those lands, towns, or provinces, which he relinquishes: and this suffices for securing the quiet possession of them to the enemy into whose hands they are fallen.

§ 12. How the sovereign may in a treaty dispose of what concerns individuals.
The necessity of making peace authorizes the sovereign to dispose of the property of individuals; and the eminent domain gives him a right to do it (Book I. § 244). He may even, to a certain degree, dispose of their persons, by virtue of the power which he has over all his subjects. But as it is for the public advantage that he thus disposes of them, the state is bound to indemnify the citizens who are sufferers by the transaction. (Ibid.)

§ 13. Whether a king, being a prisoner of war, can make peace.
Every impediment by which the prince is disabled from administering the affairs of government, undoubtedly deprives him of the power of making peace. Thus a king cannot make a treaty of peace during his minority, or while in a state of mental derangement: this assertion does not stand in need of any proof: but the question is, whether a king can conclude a peace while he is a prisoner of war, and whether the treaty thus made be valid? Some celebrated authors5 here draw a distinction between a monarch whose kingdom is patrimonial, and another who has only the usufructus of his dominions. We think we have overthrown that false and dangerous idea of a patrimonial kingdom (Book I. §§ 68, etc.), and evidently shown that the notion ought not to be extended beyond the bare power with which a sovereign is sometimes intrusted, of nominating his successor, of appointing a new prince to rule over the state, and dismembering some parts of it, if he thinks it expedient; — the whole, however, to be uniformly done for the good of the nation, and with a view to her greater advantage. Every legitimate government, whatever it be, is established solely for the good and welfare of the state. This incontestable principle being once laid down, the making of peace is no longer the peculiar province of the king; it belongs to the nation. Now it is certain that a captive prince cannot administer the government, or attend to the management of public affairs. How shall he who is not free command a nation? How can he govern it in such manner as best to promote the advantage of the people, and the public welfare? He does not, indeed, forfeit his rights; but his captivity deprives him of the power of exercising them, as he is not in a condition to direct the use of them to its proper and legitimate end. He stands in the same predicament as a king in his minority, or laboring under a derangement of his mental faculties. In such circumstances, it is necessary that the person or persons whom the laws of the state designate for the regency should assume the reins of government. To them it belongs to treat of peace, to settle the terms on which it shall be made, and to bring it to a conclusion, in conformity to the laws.

The captive sovereign may himself negotiate the peace, and promise what personally depends on him: but the treaty does not become obligatory on the nation till ratified by herself, or by those who are invested with the public authority during the prince’s captivity, or, finally, by the sovereign himself after his release.

But, if it is a duty incumbent on the state to use her best efforts for procuring the release of the most inconsiderable of her citizens who has lost his liberty in the public cause, the obligation is much stronger in the case of her sovereign, whose cares, attention, and labors are devoted to the common safety and welfare. It was in fighting for his people that the prince, who has been made prisoner, fell into that situation, which, to a person of his exalted rank, must be wretched in the extreme: and shall that very people hesitate to deliver him at the expense of the greatest sacrifices? On so melancholy an occasion, they should not demur at any thing short of the very existence of the state. But, in every exigency, the safety of the people is the supreme law; and, in so severe an extremity, a generous prince will imitate the example of Regulus, That heroic citizen, being sent back to Rome on his parole, dissuaded the Romans from purchasing his release by an inglorious treaty, though he was not ignorant of the tortures prepared for him by the cruelty of the Carthaginians.6

§ 14. Whether peace can be made with an usurper
When an unjust conqueror, or any other usurper, has invaded the kingdom, he becomes possessed of all the powers of government when once the people have submitted to him, and, by a voluntary homage, acknowledged him as their sovereign. Other states, as having no right to intermeddle with the domestic concerns of that nation, or to interfere in her government, are bound to abide by her decision, and to look no farther than the circumstances of actual possession. They may, therefore, broach and conclude a treaty of peace with the usurper. They do not thereby infringe the right of the lawful sovereign: it is not their business to examine and judge of that right: they leave it as it is, and only look to the possession in all the affairs they have to transact with that kingdom, pursuant to their own rights and those of the nation whose sovereignty is contested. But this rule does not preclude them from espousing the quarrel of the dethroned monarch, and assisting him, if he appears to have justice on his side: they then declare themselves enemies of the nation which has acknowledged his rival, as, when two different states are at war, they are at liberty to assist either party whose pretensions appear to be best founded.

§ 15. Allies included in the treaty of peace.
The principal in the war, the sovereign in whose name it has been carried on, cannot justly make a peace without including his allies, — I mean those who have given him assistance without directly taking part in the war. This precaution is necessary, in order to secure them from the resentment of live enemy: for though the latter has no right to take offence against his adversary’s allies, whose engagements were purely of a defensive nature, and who have done nothing more than faithfully execute their treaties (Book III. § 101) — yet it too frequently happens that the conduct of men is influenced by their passions rather than by justice and reason. If the alliance was not of prior date to the commencement of the war, and was formed with a view to that very war, — although these new allies do not engage in the contest with all their force, nor directly as principals, they nevertheless give to the prince against whom they have joined, just cause to treat them as enemies. The sovereign, therefore, whom they have assisted, must not omit including them in the peace.

But the treaty concluded by the principal is no farther obligatory on his allies than as they are willing to accede to it, unless they have given him full power to treat for them. By including them in his treaty, he only acquires a right, with respect to his reconciled enemy, of insisting that he shall not attack those allies on account of the succors they have furnished against him, — that he shall not molest them, but shall live in peace with them as if nothing had happened.

§ 16. Associates to treat each for himself.
Sovereigns who have associated in a war, — all those who have directly taken part in it, — are respectively to make their treaties of peace, each for himself. Such was the mode adopted at Nimeguen, at Ryswick, and at Utrecht. But the alliance obliges them to treat in concert. To determine in what cases an associate may detach himself from the alliance, and make a separate peace, is a question which we have examined in treating of associations in war (Book III. Chap. VI.), and of alliances in general (Book II. Chap. XII. and XV.).

§ 17. Mediation.
It frequently happens that two nations, though equally tired of the war, do nevertheless continue it merely from a fear of making the first advances to an accommodation, as these may be imputed to weakness; or they persist in it from animosity, and contrary to their real interests. On such occasions, some common friends of the parties effectually interpose, by offering themselves as mediators. There cannot be a more beneficent office, and more becoming a great prince, than that of reconciling two nations at war, and thus putting a stop to the effusion of human blood: it is the indispensable duty of those who have the means of performing it with success. This is the only reflection we shall here make on a subject we have already discussed (Book II. § 328).

§ 18. On what footing peace may be concluded.
A treaty of peace can be no more than a compromise. Were the rules of strict and rigid justice to be observed in it, so that each party should precisely receive every thing to which he has a just title, it would be impossible ever to make a peace. First, with regard to the very subject which occasioned the war, one of the parties would be under a necessity of acknowledging himself in the wrong, and condemning hie own just pretensions: which he will hardly do, unless reduced to the last extremity. But if he owns the injustice of his cause, he must at the same time condemn every measure he has pursued in support of it: he must restore what he has unjustly taken, must reimburse the expenses of the war, and repair the damages. And how can a just estimate of all the damages be formed: What price can be set on all the blood that has been shed, the loss of such a number of citizens, and the ruin of families! Nor is this all. Strict justice would further demand, that the author of an unjust war should suffer a penalty proportioned to the injuries for which he owes satisfaction, and such as might insure the future safety of him whom he attacked. How shall the nature of that penalty be determined, and the degree of it be precisely regulated? In fine, even he who had justice on his side may have transgressed the bounds of justifiable self-defense, and been guilty of improper excesses in the prosecution of a war whose object was originally lawful: here then are so many wrongs, of which strict justice would demand reparation. He may have made conquests and taken booty beyond the value of his claim. Who shall make an exact calculation, a just estimate of this? Since, therefore, it would be dreadful to perpetuate the war, or to pursue it to the utter ruin of one of the parties, — and since, however just the cause in which we are engaged, we must at length turn our thoughts towards the restoration of peace, and ought to direct all our measures to the attainment of that salutary object, — no other expedient remains than that of coming to a compromise respecting all claims and grievances on both sides, and putting an end to all disputes by a convention as fair and equitable as circumstances will admit of. In such conventions, no decision is pronounced on the original cause of the war, or on those controversies to which the various acts of hostility might give rise; nor is either of the parties condemned as unjust, — a condemnation to which few princes would submit; — but, a simple agreement is formed, which determines what equivalent each party shall receive in extinction of all his pretensions.

§ 19. General effect of the treaty of peace.
The effect of the treaty of peace is to put an end to the war, and to abolish the subject of it. It leaves the contracting parties no right to commit any acts of hostility on account either of the subject itself which had given rise to the war, or, of any thing that was done during its continuance: wherefore they cannot lawfully take up arms again for the same subject. Accordingly, in such treaties, the contracting parties reciprocally engage to preserve perpetual peace: which is not to be understood as if they promised never to make war on each other for any cause whatever. The peace in question relates to the war which it terminates: and it is in reality perpetual, inasmuch as it does not allow them to revive the same war, by taking up arms again for the same subject which had originally given birth to it.

A special compromise, however, only extinguishes the particular means to which it relates, and does not preclude any subsequent pretensions to the object itself, on other grounds. Care is therefore usually taken to require a general compromise, which shall embrace not only the existing controversy, but the very thing itself which is the subject of that controversy: stipulation is made for a general renunciation of all pretensions whatever to the thing in question: and thus, although the party renouncing might in the sequel be able to demonstrate by new reasons that the thing did really belong to him, his claim would not be admitted.

§ 20. Amnesty.
An amnesty is a perfect oblivion of the past; and the end of peace being to extinguish all subjects of discord, this should be the leading article of the treaty: and accordingly, such is at present the constant practice. But though the treaty should be wholly silent on this head, the amnesty, by the very nature of the peace, is necessarily implied in it.

§ 21. Things not mentioned in the treaty.
As each of the belligerent powers maintains that he has justice on his side, — and as their pretensions are not liable to be judged by others (Book III. § 188), — whatever state things happen to be in at the time of the treaty is to be considered as their legitimate state; and if the parties intend to make any change in it, they must expressly specify it in the treaty. Consequently all things not mentioned in the treaty are to remain on the same footing on which they stand at the period when it is concluded. This is also a consequence of the promised amnesty. All damages caused during the war are likewise buried in oblivion; and no action can be brought for those of which the treaty does not stipulate the reparation: they are considered as having never happened.

§ 22. Things not included in the compromise or amnesty.
But the effect of the compromise or amnesty cannot be extended to things which have no relation to the war that is terminated by the treaty. Thus, claims founded on a debt, or on an injury which had been done prior to the war, but which made no part of the reasons for undertaking it, still stand on their former footing, and are not abolished by the treaty, unless it be expressly extended to the extinction of every claim whatever. The case is the same with debts contracted during the war, but for causes which have no relation to it, — or with injuries done during its continuance, but which have no connection with the state of warfare.

Debts contracted with individuals, or injuries which they may have received from any other quarter, without relation to the war, are likewise not abolished by the compromise and amnesty, as these solely relate to their own particular object, — that is to say, to the war, its causes, and its effects. Thus, if two subjects of the belligerent powers make a contract together in a neutral country, or if the one there receives an injury from the other, — the performance of the contract, or the reparation of the injury and damage, may be prosecuted after the conclusion of the treaty of peace.

Finally, if the treaty expresses that all things shall be restored to the state in which they were before the war, this clause is understood to relate only to immovable possessions, and cannot be extended to movables, or booty, which immediately becomes the property of the captors, and is looked on as relinquished by the former owners on account of the difficulty of recognising it, and the little hope they entertain of ever recovering it.

§ 23. Former treaties, mentioned and confirmed in the new, are a part of it.
When the last-made treaty mentions and confirms other treaties of prior date, these constitute a part of the new one, no less than if they were literally transcribed and included in it: and any new articles relating to former conventions are to be interpreted according to the rules which we have laid down in a preceding part of this work (Book II. Chap. XVII. and particularly § 286).


     1.    Upon the subject of treaties in general, and their construction, see ante, book ii. ch. xii. p. 192-274. Whilst examining the sections of Vattel relative to treaties, it will be found advisable to read the modern treaties, which are collected in Chitty’s Commercial Law, latter part of vol. 2. — C.
     2.    Ante, 292-2; and see Hoop, 1 Rob. Rep. 196, Id.; 1 Chitty’s Com. L. 378. — C.
     3.    The abbé de Choisi, Hist. de Charles V. p. 492.
     4.    The renunciation made by Anne of Austria, consort of Louis the Thirteenth, was good and valid, because it was confirmed by the general assembly of the Cortes, and registered in all the offices. The case was otherwise with that made by Anna Theresa, which was not sanctioned by those formalities — consequently, not stamped with the national approbation, and the character of a law of the state. The cardinals who examined this affair by order of the pope, whom Charles II. had consulted, paid no regard to Maria Theresa’s renunciation, as not deeming it of sufficient force to invalidate the laws of the country, and to supersede the established custom. — Memoirs of M. de St. Philippe, vol. i. p. 29. — Ed. A.D. 1797.
     5.    See Wolf. Jus Gent. § 982.
     6.    See Tit. Liv. Epitom. lib. xviii. and other historians.