Of all the differences between a pirate and a privateer, the most important — and, in my experience, the most poorly understood — was a single sheet of vellum, signed by a state official, often half-illegible by the time it reached the actual sea where it might matter. The Letter of Marque, or Letter of Marque and Reprisal, was the document that converted private maritime violence into a legitimate adjunct of state policy. It was also, much of the time, an exercise in elaborate political theatre, useful chiefly for protecting one's neck if captured by the wrong navy.

What I want to do here is walk through the mechanics of the system as it actually operated in the long seventeenth and early eighteenth centuries, using as a guide the surviving admiralty papers of Bermuda, which are a remarkably complete set of records for a small but commercially significant English Atlantic colony. The Bermuda papers are now held at the National Archives at Kew under CO 37 and HCA 49; I have spent altogether too much time with them, and I have come away thinking that the system was both more interesting and more grimly bureaucratic than the popular picture suggests.

What a letter actually said

A typical late-seventeenth-century English letter of marque was a printed document with manuscript additions, perhaps fifteen inches by twenty, signed by the Lord High Admiral or his designated representative, and sealed in red wax. It identified by name the ship to be commissioned, the captain, the tonnage, the armament, the names of the principal owners and their sureties, and the specific enemy whose vessels the letter authorised the bearer to attack.

That last point is important and often missed. A letter of marque was not a general license to commit acts of war. It was specific: against Spanish shipping during the Anglo-Spanish wars, against French shipping during the wars of the 1690s and 1700s, against the Dutch during the three Anglo-Dutch wars, and so forth. Attacking the wrong nation's shipping, even with a valid letter, was an act of piracy that could be — and frequently was — prosecuted.

The letter also required the captain to enter into a recognisance, or bond, typically of one thousand pounds, guaranteed by two sureties of substance. This was the financial mechanism that, in theory, kept privateers honest: if the captain misbehaved — attacked neutral shipping, exceeded the terms of his commission, failed to deliver his prizes to a proper admiralty court for adjudication — the bond was forfeit. In practice, the sureties were often the same merchants who owned shares in the privateering venture, which limited the deterrent considerably.

The prize court

Here is where the system becomes genuinely interesting, and where it begins to resemble a kind of early modern arbitrage operation rather than the romantic picture of dashing captains and reckless adventure.

When a privateer captured a vessel, it could not simply distribute the goods to the crew. The capture had to be brought into a port with a duly-constituted Vice-Admiralty Court, where the captured ship and cargo would be formally adjudicated. This was a legal proceeding, often quite a lengthy one, in which the prize-taker's claim to the captured property had to be proven against the standards of admiralty law.

The court would examine the privateer's commission to verify that it was valid and current. It would examine the captured ship's papers to determine its nationality, its cargo, and its destination. It would hear depositions from the captured ship's master and crew — who had a legal right to be heard, and who were sometimes represented by counsel. It would consider whether the captured goods were the property of enemy subjects (lawful prize), neutral subjects (which complicated matters considerably and often required restoration of the goods at the privateer's expense), or, occasionally, the privateer-taker's own countrymen (which was outright piracy).

The Snow Mary, lately of Saint-Malo, taken on the 4th day of June by Captain Whittall in the sloop Two Brothers, is condemned good and lawful prize, the said vessel being clearly of French registry and the said cargo of brandy and dry goods being demonstrably the property of subjects of the French king; saving however unto the proctors of the said Whittall the customary tenth part for the Lord High Admiral... — BERMUDA VICE-ADMIRALTY COURT, JUDGEMENT OF 17 JUNE 1697

This is the standard form. Note the deductions. Before the privateering crew saw a penny, the Crown took its tenth (the Lord High Admiral's share, paid effectively to the central government). The Vice-Admiralty Court took its fees, which could run to ten or fifteen per cent of the gross. The colonial governor took a discretionary share, usually around five per cent. Auctioneers' fees, customs duties, warehousing charges, and the cost of provisioning the prize crew during the legal proceedings all came off the top.

The result, in a well-documented Bermuda case from 1702 that I have followed through the papers, was that a French prize valued at the time of capture at approximately four thousand pounds sterling yielded to the privateering crew of forty-one men a total distribution of one thousand four hundred and twelve pounds — about thirty-five per cent of the original gross. After the captain's double share and the owners' two-thirds entitlement to the crew's portion, the per-man payment for the ordinary seaman was eight pounds, eleven shillings. This was, to be clear, an excellent payment by the standards of merchant service — perhaps a year's wages — but it was nothing like the popular image of pirate riches.

What this system was for

It is tempting, from a modern perspective, to read the early modern privateering regime as a kind of grudging accommodation between states and what they could not suppress — a way of channelling violence that would have happened anyway into a controlled form. I think this is roughly half right.

The other half is that privateering was an absolutely deliberate instrument of state policy, particularly for states whose naval establishments could not afford to bear the entire cost of wartime maritime operations. For the English Crown in the 1690s and 1700s, every French merchantman taken by a privateer was a French merchantman the Royal Navy did not have to chase. The Crown's tenth share of the proceeds — paid promptly and reliably by the admiralty courts — was a not-insignificant contribution to wartime revenues. And the bond requirement meant that the political and economic risk of privateering operations was borne not by the state but by colonial merchants, whose capital was effectively conscripted into the war effort.

This was, in other words, public-private partnership in a fairly recognisable modern sense. The state set the legal framework and took a tax. The private capital took the operational risk. The crews bore the physical risk and received the smallest individual share of the upside. The system was not invented by the late Stuarts — its medieval origins go back to the thirteenth century — but it reached its mature commercial form between roughly 1650 and 1715, before declining in importance over the eighteenth century as professional navies grew and as the legal status of privateering became increasingly contested.

The line that mattered

The line between privateer and pirate, in the long seventeenth century, was almost entirely paperwork. The same man — Henry Morgan is the canonical example, but he was far from unique — could be a privateer one year, a pirate the next, and a knighted royal official the year after that, depending on what documents he carried, what wars were ongoing, and what political calculations were being made in Whitehall.

The men who were eventually hanged as pirates in the great cleanups of the 1710s and 1720s — Rackham, Bonnet, Roberts and the rest — were operating in a system that had, within their own lifetimes, treated their direct predecessors as legitimate auxiliaries of the state. The change was partly about war and peace (a state at peace has no need for privateers), partly about the rising strength of professional navies, and partly about a growing reluctance, on both sides of the Atlantic, to tolerate the political and economic externalities that an undisciplined privateering establishment created.

What I find most striking about the documents is that nobody at the time seems to have thought the system was particularly stable. The Bermuda papers are full of correspondence between governors, admirals, and merchant captains expressing varying degrees of dismay about its workings — about commissioners who took bribes, about prize courts that issued condemnations they should not have, about privateers who exceeded their commissions, and about a general atmosphere of legalised acquisitiveness that was, by 1700, beginning to make even committed defenders of the system uncomfortable. It died, in the end, not from any single reform but from the gradual realisation, on all sides, that there were better ways to fight wars at sea.

A note on the sources

The Bermuda Vice-Admiralty Court records are at the National Archives at Kew (HCA 49/82–87 for the relevant period). The introductory volume of the Hakluyt Society's Documents Relating to Law and Custom of the Sea, edited by R. G. Marsden, is the best printed starting point for English privateering law. For the political-economic side, the most thorough recent treatment is David J. Starkey's British Privateering Enterprise in the Eighteenth Century, which despite its title contains substantial coverage of the late-Stuart background.