International Judicial Monitor
Published by the International judicial Academy of the International Law Institute, Washington, D.C.
with circulation assistance from the American Society of International Law

Summer 2017 Issue

Historic Moments in International Law

Profiting from War:  The Law and Practice of Medieval Prisoner Ransom

Stephen C. NeffBy: Stephen C. Neff, Reader-in- Law, Public International Law, University of Edinburgh Law School

The valiant Achilles – that paragon of Greek warrior-heroes – is not ordinarily associated with economic entrepreneurship or war profiteering.  But Homer, in the Iliad, recounts an interesting incident in his colorful career.  In a daring night raid against Troy, Achilles captured Lycaon, one of the many (fifty) sons of King Priam.  He then proceeded to sell his royal captive into slavery in Lemnos, for the tidy sum of one hundred oxen.  The purchaser, incidentally, was Eunus, the son of another Greek hero, Jason (of golden-fleece fame).  Fortunately for Lycaon, however, a “guest-friend” purchased him from Eunus, this time for the worth of three hundred oxen, thereby enabling him to return to the fray at Troy.

The incident of Lycaon was not, strictly speaking, a ransom arrangement, since Lycaon did not secure his freedom directly from Achilles in exchange for money.  In the course of time, though, a fully fledged practice – one could even call it something of an industry – of prisoner ransom arose in the European Middle Ages.  Central to it was the notion that prisoners of war belonged, in law, to the individual parties who captured them.  Captives were regarded, with good reason, as valuable commodities, chiefly for the ransoms which they could fetch.  So important was this process of ransoming prisoners that a very elaborate body of law and practice grew up around it.

Ransoming involved individual negotiations over terms between the immediate parties.  But it also involved the governments, since it had an impact on the overall war effort.  From the standpoint of the captive’s home state, there was concern over the transfer of resources to the enemy side for the ransoming.  Conversely, the captor side could be concerned that a ransomed prisoner was then free to rejoin the conflict and augment the opposing forces.  For this reason, ransoming was sometimes not allowed.  A famous example was at the Battle of Agincourt in 1415, where prisoners were ordered to be killed – to the great financial detriment of the victors.  In general, though, the prospect of capturing a high-ranking enemy combatant and reaping the glittering reward of a ransom was part of the allure of medieval warfare.

At every step of the way, legal considerations played a role.  More specifically, an amalgamation of two bodies of law was applicable.  One was the law of arms, which was a transnational legal code governing warfare – a kind of medieval analogue of the present-day Hague and Geneva Conventions.  This set out the general rules of conduct for captors and prisoners.  The other was the law of contract.  This was part of general natural law, which was held to be binding on all persons without regard to diversity of political allegiance.  It governed the specific arrangements agreed between captor and prisoner.

A first step was determining who, legally, was the captor.  It was not, or not necessarily, the person who took the prisoner into his physical custody.  According to the law of arms, the lawful captor was the person to whom the captive gave his word of honor, to be a good and loyal prisoner and faithfully to keep his word.  This might not be the person who initially took physical custody of the prisoner because feudal underlings were required to turn any captives over to their superiors, to whom the requisite word of honor would then be given.  The commitments were typically reduced to writing, in what were called, appropriately enough, letters of obligation.  In principle, these agreements were reciprocal, so that a breach of the conditions by the captor would release the prisoner from his obligations.

A highly crucial step in this process was, of course, determining the amount of the ransom.  On this, a concept of just price was operative, at least in theory.  The Italian scholar Alberico Gentili, writing at the end of the Sixteenth Century, held that a ransom price should be “moderate” and that a captor should refrain from exacting “as much as he could” from his unfortunate charge.  Especially reprehensible, in Gentili’s eyes, was the infliction of cruel treatment onto a prisoner, with a view to increasing the ransom that he was willing to pay.

So far as can be gathered, the just price envisaged by the lawyers was a sum that was reasonably proportionate to the prisoner’s ability to pay.  In practice, however, captors were typically not so forbearing; not surprisingly, they tended to err on the high side when negotiating for ransoms.  Payments in instalments were commonly arranged, sometimes with harsh penalty provisions if the payment schedules were not rigorously met.

The rates naturally varied according to the rank and worth of the captive.  A mere archer fetched, on average, a paltry £2.  Slightly – but not much – higher on the scale was the famous literary figure Geoffrey Chaucer, who was captured in France during the Hundred Years War.  He was ransomed by his employer, King Edward III, for the less-than-princely sum of £16.  For noble prisoners, the prices were naturally much higher.  A practice appears to have evolved, of fixing ransoms at about one year’s revenue from the captive’s estate.

At the very highest levels, the sums involved could be huge – and most of all when royal personages fell into enemy hands.  In 1250, King Louis IX of France was captured in Egypt while crusading (unsuccessfully, it

need hardly be added).  A ransom of 400,000 livres tournois was negotiated – amounting to about a third of his country’s annual revenue at the time.  The money was duly paid.

Things often went less smoothly, however.  When King John II of France was captured by his English foes at the Battle of Poitiers in 1356, in the early stages of the Hundred Years War, he was taken to England.  It was another four years before the ransom was fixed, by the Treaty of Brétigny of 1360, at three million gold crowns (£667,000).  John was then allowed to return to France to raise the money, leaving his son in his stead as a hostage.  The payment of this enormous sum involved the minting of a new gold coinage – which became known as the “franc” in honor of the goal of gaining the monarch’s freedom.  The payment, however, fell into arrears.  In addition, John’s son absconded.  Ashamed of his offspring’s dishonorable conduct, John voluntarily returned to England, where his gallantry was widely admired and celebrated.  He died shortly thereafter, still in English custody.  Ransom payments continued, but only in small amounts – and about half of it remained unpaid.

The correlative rights and obligations involved in ransom payments were regarded as property rights of the most absolute kind, akin to the absolute dominium of Roman law.  This had a number of interesting logical consequences.  One was that these rights were transferable to other parties (although sometimes the consent of commanders would be required for transfers).    Also, both the right to receive, and the duty to pay, the ransom were heritable.  If either party died, his heirs stepped into his shoes.  Interference with the rights of captors by third parties was also actionable.  If, for example, a person killed a captor’s prisoner, then he became liable himself for the prisoner’s ransom.  In addition, the prisoner’s duties to his captor were regarded as prevailing over any other inconsistent obligation, such as his feudal duties to his own lord back home.

Prisoners were not always physically confined.  The basic rule was that confinement was permitted, but only to the extent necessary to ensure payment of the ransom.  The fact that prisoners were liable for the costs of their own upkeep helped to assure a modicum of comfort.  Prisoners could even be released back to their home countries for the purpose of raising their ransoms (as in the case of John II), though there was obviously a certain risk from the captor’s part in allowing this.  Captors usually issued letters to their prisoners in these cases, setting out the terms of the release, to prevent the erstwhile detainee from falsely claiming that he had been liberated.  The released prisoners also had to be provided with safe-conducts to them to travel without molestation back to their homes. 

Sometimes, as with John II, substitutes could be provided for the prisoner as hostages.  This could be a harrowing business, however, especially for low-ranking persons.  In the 1430s or 1440s, when some Bretons held a number of English hostages, a default in the agreed ransom payment led to one of the hostages being hurled over the town wall.

It was common practice too to arrange for sureties to pay the ransom to the captor, with the liberated prisoner then becoming obligated to indemnify his saviors for the money expended.  A contested question was the question of whether the duty of the sureties to pay the captor continued to apply after a prisoner’s death.  There was a split of authority on that delicate subject.  Gentili, however, insisted that the sureties were not discharged in such an event.

Also problematic were questions of escape and rescue.  A person who was captured, but immediately slipped off and was then captured a second time, belonged to the second captor rather than the first one – provided that the escape took place during the battle.  If, however, the escape and second capture occurred subsequent to the battle, then the prisoner continued to belong to the first captor; and any person who later apprehended him had to return him.

It was typically part of the arrangement that the prisoner would give his word of honor not to attempt to escape.  He therefore could be safely left unguarded – or at least as safely as his word of honor was worth.  But questions arose as to what happened if some third party intruded onto the scene with a view to rescuing the prisoner.  Was the prisoner legally obligated to resist or refuse rescue?  Here too, there was uncertainty.  One way of resolving it was to make advance provision, in which the prisoner would promise to remain legally bound to his captor even if rescued – so that he would continue to be liable for the ransom payment and would be obligated not to rejoin his forces for further participation in the war.

If and when the agreed ransom was duly paid, the erstwhile captive’s letter of obligation would be returned to him, and he was now free to rejoin his forces and continue the war.  This, of course, was no guarantee of happiness ever after, as illustrated by the case of Lycaon.  Just twelve days after his return to Troy, he was killed in battle -- by none other than Achilles.

Readers who wish a fuller account of this fascinating aspect of medieval warfare may usefully consult Maurice Keen, The Laws of War in the Late Middle Ages (1965), which has a chapter on the subject.  A more recent, and excellent, work is Rémy Ambühl, Prisoners of War in the Hundred Years War: Ransom Culture in the Late Middle Ages (2013).  Alas, a comprehensive history of profiting from war is one of those fascinating books that is yet to be written.  Perhaps some loyal reader of this column will one day fill this glaring gap.

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