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

Emmerich de Vattel

Of the Execution of the Treaty of Peace

§ 24. When the obligation of the treaty commences.
A TREATY of peace becomes obligatory on the contracting parties from the moment of its conclusion, — the moment it has passed through all the necessary forms: and they are bound to have it carried into execution without delay.1 From that instant all hostilities must cease, unless a particular day has been specified for the commencement of the peace. But this treaty does not bind the subjects until it is duly notified to them. The case is the same in this instance as in that of a truce (Book II. § 239). If it should happen that military men, acting within the extent of their functions and pursuant to the rules of their duty, commit any acts of hostility before they have authentic information of the treaty of peace, it is a misfortune, for which they are not punishable: but the sovereign, on whom the treaty of peace is already obligatory, is bound to order and enforce the restitution of all captures made subsequent to its conclusion: he has no right whatever to retain them.

§ 25. Publication of the peace.
And in order to prevent those unhappy accidents, by which many innocent persons may lose their lives, public notice of the peace is to be given without delay, at least to the troops. But at present, as the body of the people cannot of themselves undertake any act of hostility, and do not personally engage in the war, the solemn proclamation of the peace may be deferred, provided that care be taken to put a stop to all hostilities: which is easily done by means of the generals who direct the operations, or by proclaiming an armistice at the head of the armies. The peace of 1735, between the emperor and France, was not proclaimed till long after. The proclamation was postponed till the treaty was digested at leisure, — the most important points having been already adjusted in the preliminaries. The publication of the peace replaces the two nations in the state they were in before the war. It again opens a free intercourse between them, and reinstates the subjects on both sides in the enjoyment of those mutual privileges which the state of war had suspended. On the publication, the treaty becomes a law to the subjects: and they are thenceforward bound to conform to the regulations stipulated therein. If, for instance, the treaty imports that one of the two nations shall abstain from a particular branch of commerce, every subject of that nation, from the time of the treaty’s being made public, is obliged to renounce that commerce.

§ 26. Time of the execution.
When no particular time has been assigned for the execution of the treaty, and the performance of the several articles, common sense dictates that every point should be carried into effect as soon as possible: and it was, no doubt, in this light that the contracting parties understood the matter. The faith of treaties equally forbids all neglect, tardiness, and studied delays, in the execution of them.

§ 27. A lawful excuse to be admitted.
But in this affair, as in every other, a legitimate excuse, founded on a real and insurmountable obstacle, is to be admitted; for nobody is bound to perform impossibilities. The obstacle, when it does not arise from any fault on the side of the promising party, vacates a promise which cannot be made good by an equivalent, and of which the performance cannot be deferred to another time. If the promise can be fulfilled on another occasion, a suitable prolongation of the time must be allowed. Suppose one of the contracting nations has, by the treaty of peace, promised the other a body of auxiliary troops: she will not be bound to furnish them, if she happen to stand in urgent need of them for her own defense. Suppose she has promised a certain yearly quantity of corn: it cannot be demanded at a time when she herself labors under a scarcity of provisions; but, on the return of plenty, she is bound to make good the quantity in arrear, if required.

§ 28. The promise is void when the party to whom it was made has himself hindered the performance of it.
It is further held as a maxim, that the promiser is absolved from his promise, when, after he has made his preparations for performing it according to the tenor of his engagement, he is prevented from fulfilling it, by the party himself to whom it was made. The promisee is deemed to dispense with the fulfillment of a promise of which he himself obstructs the execution. Let us therefore add, that if he who had promised a thing by a treaty of peace was ready to perform it at the time agreed on, or immediately and at a proper time if there was no fixed term, — and the other party would not admit of it, the promisor is discharged from his promise: for the promisee, not having reserved to himself a right to regulate the performance of it at his own pleasure, is accounted to renounce it by not accepting of it in proper season and at the time for which the promise was made. Should he desire that the performance be deferred till another time, the promisor is in honor bound to consent to the prolongation, unless he can show by very good reasons that the promise would then become more inconvenient to him.

§ 29. Cessation of contributions.
To levy contributions is an act of hostility which ought to cease as soon as peace is concluded (§ 24). Those which are already promised, but not yet paid, are a debt actually due; and, as such, the payment may be insisted on. But, in order to obviate all difficulty, it is proper that the contracting parties should clearly and minutely explain their intentions respecting matters of this nature; and they are generally careful to do so.

§ 30. Products of the thing restored or ceded.
The fruits and profits of those things which are restored by a treaty of peace are due from the instant appointed for carrying it into execution: and if no particular period has been assigned, they are due from the moment when the restitution of the things themselves was agreed to: but those which were already received or become payable before the conclusion of the peace, are not comprised in the restitution; for the fruits and profits belong to the owner of the soil; and, in the case in question, possession is accounted a lawful title. For the same reason, in making a cession of the soil, we do not include in that cession the rents and profits antecedently due. This Augustus justly maintained against Sextus Pompey, who, on receiving a grant of the Peloponnesus, claimed the imposts of the preceding years.2

§ 31. In what condition things are to be restored.
Those things, of which the restitution is, without further explanation, simply stipulated in the treaty of peace, are to be restored in the same state in which they were when taken: for the word “restitution” naturally implies that every thing should be replaced in its former condition. Thus, the restitution of a thing is to be accompanied with that of all the rights which were annexed to it when taken. But this rule must not be extended to comprise those changes which may have been the natural consequences and effects of the war itself and of its operations. A town is to be restored in the condition it was in when taken, as far as it still remains in that condition at the conclusion of the peace. But if the town has been razed or dismantled during the war, that damage was done by the right of arms, and is buried in oblivion by the act of amnesty. We are under no obligation to repair the ravages that have been committed in a country which we restore at the peace; we restore it in its existing state, but, as it would be a flagrant perfidy to ravage that country after the conclusion of the peace, the case is the same with respect to a town whose fortifications have escaped the devastation of war: to dismantle it previous to the restoration would be a violation of good faith and honor. If the captor has repaired the breaches, and put the place in the same state it was in before the siege, he is bound to restore it in that state. If he has added any new works, he may indeed demolish these: but if he has razed the ancient fortifications, and constructed others on a new plan, it will be necessary to come to a particular agreement respecting this improvement, or accurately to define in what condition the place shall be restored. Indeed this last precaution should in every case be adopted, in order to obviate all dispute and difficulty. In drawing up an instrument solely intended for the restoration of peace, it should be the object of the parties to leave, if possible, no ambiguity whatever, — nothing which may have a tendency to rekindle the flames of war. I am well aware, however, that this is not the practice of those who value themselves now-a-days on their superior abilities in negotiation: on the contrary, they study to introduce obscure or ambiguous clauses into a treaty of peace, in order to furnish their sovereign with a pretext for broaching a new quarrel and taking up arms again on the first favorable opportunity. How contrary such pitiful finesse is to the faith of treaties, we have already observed (Book II, § 231): it is a disparagement of that candor and magnanimity which should beam forth in all the actions of a great prince.

§ 32. The interpretation of a treaty of peace is to be against the superior party.3
But, as it is extremely difficult wholly to avoid ambiguity in a treaty, though worded with the greatest care and the most honorable intentions, — and to obviate every doubt which may arise in the application of its several clauses to particular cases, — recourse must often be had to the rules of interpretation. We have already devoted an entire chapter to the exposition of those important rules:4 wherefore, instead of entering at present into tedious repetitions, we shall confine ourselves to a few rules more particularly adapted to the special case before us, — the interpretation of treaties of peace. 1. In case of doubt, the interpretation goes against him who prescribed the terms of the treaty: for as it was in some measure dictated by him, it was his own fault if he neglected to express himself more clearly: and by extending or restricting the signification of the expressions to that meaning which is least favorable to him, we either do him no injury, or we only do him that to which he has wilfully exposed himself; whereas, by adopting a contrary mode of interpretation, we would incur the risk of converting vague or ambiguous terms into so many snares to entrap the weaker party in the contract, who has been obliged to subscribe to what the stronger had dictated.

§ 33. Names of ceded countries.
2. The names of countries ceded by treaty are to be understood according to the usage prevailing at the time among skillful and intelligent men: for it is not to be presumed that weak or ignorant persons should be intrusted with so important a concern as that of concluding a treaty of peace; and the articles of a contract are to be understood of what the contracting parties most probably had in contemplation, since the object in contemplation is the motive and ground of every contract.

§ 34. Restoration not to be understood of those who have voluntarily given themselves up.
3. The treaty of peace naturally and of itself relates only to the war which it terminates. It is, therefore, in such relation only, that its vague clauses are to be understood. Thus, the simple stipulation of restoring things to their former condition does not relate to changes which have not been occasioned by the war itself: consequently, this general clause cannot oblige either of the parties to set at liberty a free people who have voluntarily given themselves up to him during the war. And as a people, when abandoned by their sovereign, become free, and may provide for their own safety in whatever manner they think most advisable (Book I. § 202) — if such people, during the course of the war have voluntarily, and without military compulsion, submitted and given themselves up to the enemy of their former sovereign, the general promise of restoring conquests shall not extend to them. It were an unavailing plea, to allege that the party who requires all things to be replaced on their former footing may have an interest in the independence of the former of those people, and that he evidently has a very great one in the restoration of the latter. If he wished to obtain things which the general clause does not of itself comprise, he should have clearly and specifically expressed his intentions relative to them. Stipulations of every kind may be inserted in a treaty of peace; but if they bear no relation to the war which it is the view of the contracting parties to bring to a conclusion, they must be very expressly specified; for the treaty is naturally understood to relate only to its own particular object.


     1.    It is an essential point to neglect none of the formalities which can insure the execution of the treaty, and prevent new disputes. Accordingly, care must be taken to have it duly recorded in all the proper offices and courts. M. Van Benningen, writing to the Grand Pensionary De Witt, in 1662, thus observes — “The articles and conditions of this alliance contain various matters of different natures, the majority of which fall under the cognizance of the privy council, — several under that of the civil tribunals, the parliaments, etc. — escheatage, for instance, which comes under the cognizance of des comptes [exchequer]. Thus, the treaty must be recorded in all those different places.” This advice was followed; and the states-general required that the treaty conducted the same year should be recorded in all the parliaments of the kingdom. See the king’s reply on this subject, in his letter to the Count D’Estrades, page 399. — Edit A.D. 1797.
     2.    Applan, de Bell. Civ. lib. v., quoted by Grotius, lib. ii. cap. 20, § 22.
     3.    As to the construction of treaties in general, see Book II. Chap. XVII. § 262, ante, 244. — C.
     4.    Book II. Chap. XVII. ante, 244-274.