The memoirs of European slaves in Islamic North Africa were long dismissed as little more than “pitiful tales.” Yet recent international studies have demonstrated that the enslavement of Christians in “Barbary” was by no means a marginal phenomenon, and that the fate of these captives was far from enviable.

In 2004, the French historian Olivier Pétré-Grenouilleau published his influential work Les traites négrières (The Slave Trade). In it, he devoted attention not only to the European slave trade, but also to indigenous African and Arab slave trading systems. Moreover, he argued that the latter two were even larger in scale than their transatlantic counterpart. His conclusions provoked furious reactions from descendants of Black slaves.

They accused Pétré-Grenouilleau of trivialising the transatlantic slave trade by placing it on the same level as other forms of slavery. According to his critics, the transportation of slaves to the New World constituted a unique form of “genocide,” ultimately comparable only to the Holocaust. The historian was accused of “revisionism,” and although the charges were later withdrawn after strong protests from fellow French historians, the tone of the debate had been set.

Two years later, another group of French citizens — migrants from North Africa and their descendants — reacted with shock to a historical study. This time it concerned the French translation of a work by Robert C. Davis. In his book Christian Slaves, Muslim Masters, the American historian examined the North African trade in Christian slaves, applying research models that had previously been used almost exclusively for the transatlantic slave trade. In his study, Davis not only challenged the widespread belief that European slaves in North Africa were generally treated relatively well, but also presented striking overall figures regarding the scale of the phenomenon.

The persistent underestimation of slavery in the Arab world has resulted in comparatively little research being devoted to the subject. Historical studies of the Middle East have generally been remarkably sparse in their treatment of Arab slavery. Only in recent years have serious attempts been made to chart this vast and complex phenomenon.

Text from: 'The Scale of Christian Slavery Underestimated, by Maurice Blessing, Historisch Nieuwsblad 5/2008

Dutch and English war frigates engaged in battle with Barbary corsairs — Laureys a Castro, A Sea Fight with Barbary Corsairs (1681).

Thereafter, the history of the “trade in white slaves” gradually began to receive greater scholarly attention, although the subject still receives relatively little coverage in the press.

According to recent research, an estimated 1.25 million Western Europeans were captured and enslaved by the Barbary corsairs between the sixteenth and nineteenth centuries. This estimate does not include Christian slaves held in independent Morocco (with the corsair ports of Tetouan and Salé), nor those in Turkey and Egypt. According to the Turkish historian Halil İnalcık, the Ottoman Empire alone imported some 2.5 million Eastern European slaves via the Crimea between 1450 and 1700.

At the height of Barbary corsair activity, roughly 20,000 to 30,000 Christian slaves were continuously held in Algiers — approximately a quarter of the city’s population. The majority never returned home. According to an estimate by the American historian Robert C. Davis, the annual mortality rate was around 17 percent, in addition to the mere 8 percent who were ransomed, escaped, or disappeared into local society as “renegades” — converts to Islam.

Very little research has yet been conducted into the number of Dutch citizens who were enslaved. Estimates range from several tens of thousands to around 7,000. This latter figure, however, refers only to the crews of Dutch merchant vessels who ended up enslaved in Algiers, and even then only over the course of a single century — the seventeenth. Comparable figures for Tunis, Tetouan, and Salé are lacking.

The number of Dutch victims must nevertheless have been substantial, simply because there were so many Dutch ships at sea compared to those of other maritime nations. By 1600, the Dutch already possessed approximately 1,900 seagoing vessels of one hundred tons or more — nearly five times the number owned by the English. During the seventeenth century, the vast majority of Western European trade was carried by Dutch ships. They dominated not only commerce between Spain, France, England, and the Baltic, but also much of the coastal trade between French ports themselves. At its peak between 1660 and 1670, the merchant fleet of the Dutch Republic consisted of roughly 2,600 seagoing ships exceeding one hundred tons. By then, the English fleet had grown to approximately 1,400 vessels.

An English observer, John Keymor, estimated the Dutch fleet in 1601 at 20,000 vessels, though this included not only merchantmen but also coastal craft and, among others, some 4,100 fishing boats.

The French diplomat Sanson Napollon reported the number of ships captured by Algerian corsairs between 1613 and 1621. He arrived at a total of 936 vessels, of which 447 were of Dutch origin. British archival research shows that between 1609 and 1616 alone, approximately 466 English ships were captured. Figures have also survived for the years 1677–1680: during those three years, 160 English vessels were taken by the Algerians, resulting in an estimated 7,000 to 9,000 English captives. Given the far greater number of Dutch ships at sea, the number of Dutch citizens enslaved must have been at least equally significant.

Dutch, English, and French captives consisted primarily of sailors and passengers and in fact represented only a small proportion of the total slave population. Most victims came from the Mediterranean region — the coasts of Spain and Italy and the islands of the Mediterranean — where entire coastal towns and villages were at times plundered and depopulated.

Although precise historical figures are lacking, it is possible to estimate roughly how many “fresh” slaves were needed annually to maintain stable captive populations and replace those who had died, been ransomed, escaped, or converted to Islam. On this basis, historians estimate that approximately 8,500 new slaves were required each year. Calculated over the 250-year period between 1530 and 1780, this would amount to more than two million people. Robert Davis, as noted above, places the total at 1.25 million.

Sources: Ohio State News, Christian Slaves, Muslim Masters, 'Privateers and Merchants (Gerard van Krieken), Barbarijse Piraten, Observation Made Upon The Dutch Fishing (John Keymore), BBC History, British Slaves on the Barbary Coast

The policy of the Dutch government was aimed at concluding peace treaties with the Barbary states — with only limited success. During the seventeenth century, treaties with Algiers were in force for a total of merely seventeen years. For the remaining eighty-three years, Algerian corsairs were free to prey upon Dutch shipping without restriction — and they did so extensively.

Only in 1816 did the bombardment of Algiers by a combined British and Dutch fleet bring the Algerian slave trade to an end. Following the attack, more than four thousand Christian slaves were liberated.

Bombardment of Algiers in 1816, Thomas Luny (1820)

The small percentage of white slaves who were eventually ransomed fell into three distinct categories.

Captains and mates insured through one of the Dutch Buidels van Assurantie (insurance funds established in places such as Amsterdam, South Holland, Groningen, and Friesland) could generally count on relatively swift redemption and comparatively favourable treatment. Their ransom was also more or less fixed, amounting to approximately 2,000 to 2,500 guilders. Once the insurance funds had been paid, they were permitted to return to the Dutch Republic.

Wealthy civilians, by contrast, were subjected to prolonged negotiations in which the ransom demanded was determined according to their perceived financial means. They often became part of the household of their owner as servants, though they were by no means always treated humanely. For the “master,” time was of little importance: he would rather keep a slave captive for years than make concessions regarding the ransom price. Every last coin was squeezed from the negotiations.

For ordinary people — and especially for common sailors — there was only occasional hope of return. They depended upon lotteries and charitable collections that were sometimes organised in the homeland by municipalities, churches, or private citizens. In the town of Zierikzee, for example, a slave relief fund was established in 1735.

Only very sporadically were public funds made available for the redemption of captives. The Dutch government maintained that the liberation of slaves was not a matter of state responsibility. In principle, it did not ransom slaves. Sailors and shipowners were considered responsible for their own safety. The government’s principal consideration was, naturally, the expense involved. Moreover, it feared that large-scale ransom payments would only further encourage piracy.

The result was that only wealthy Dutch citizens were regularly redeemed. The remainder — the overwhelming majority — were usually condemned to spend the rest of their lives in slavery.

Ordinary sailors and others with little prospect of redemption were confined in the bagnios, special prisons of which eight were in operation during the seventeenth century, the period in which the book is set. During the day they were put to work. The fortunate ones were assigned to sail lofts or ropewalks; the rest laboured in the harbour, where captured ships were often dismantled down to the keel, or worse still, in the stone quarries near Algiers.

Slaves who had reached the end of their strength, or who had in some way lost the confidence of their masters, were sold on to Turkish galleys. There, chained to the oars, only a short future remained to them; anyone sent to the galleys was effectively condemned to death.

Photograph of the remains of the quarry just outside Algiers, where two characters from In Barbary were put to work. The photograph was provided by reader Nick Elzinga, who travelled through Algeria in 2022.

In 1678 — the year in which the book is set — Algiers held 420 Dutch slaves. Between 1678 and 1680, another 300 Dutchmen and 300 sailors of other nationalities were added to this number, having been captured aboard twenty-eight Dutch and Zeeland merchant vessels. Of the total of 1,020 captives, only 239 eventually returned to the Dutch Republic in 1683.