North African pirates abducted and enslaved more than 1 million Europeans between 1530 and 1780 in a series of raids which depopulated coastal towns from Sicily to Cornwall, according to new research.
Thousands of white Christians were seized every year to work as galley slaves, labourers and concubines for Muslim overlords in what is today Morocco, Tunisia, Algeria and Libya, it is claimed.
Scholars have long known of the slave raids on Europe. But American historian Robert Davis has calculated that the total number captured - although small compared with the 12 million Africans shipped to the Americas in later years - was far higher than previously recognised.
His new book, Christian Slaves, Muslim Masters: White Slavery in the Mediterranean, the Barbary Coast, and Italy, 1500-1800, concluded that 1 million to 1.25 million ended up in bondage.
Prof Davis's unorthodox methodology split historians over whether his estimates were plausible but they welcomed any attempt to fill a gap in the little-known story of Africans subjugating Europeans.
By collating different sources of information from Europe over three centuries, the University of Ohio professor has painted a picture of a continent at the mercy of pirates from the Barbary Coast, known as corsairs, who sailed in lateen-rigged xebecs and oared galleys.
Villages and towns on the coast of Italy, Spain, Portugal and France were hardest hit but the raiders also seized people in Britain, Ireland and Iceland. According to one account they even captured 130 American seamen from ships that they boarded in the Atlantic and Mediterranean between 1785 and 1793.
In the absence of detailed written records such as customs forms Prof Davis decided to extrapolate from the best records available indicating how many slaves were at a particular location at a single time and calculate how many new slaves were needed to replace those who died, escaped or were freed.
To keep the slave population stable, around one quarter had to be replaced each year, which for the period 1580 to 1680 meant around 8,500 new slaves per annum, totalling 850,000.
The same methodology would suggest 475,000 were abducted in the previous and following centuries.
"Much of what has been written gives the impression that there were not many slaves and minimises the impact that slavery had on Europe," Prof Davis said in a statement this week.
"Most accounts only look at slavery in one place, or only for a short period of time. But when you take a broader, longer view, the massive scope of this slavery and its powerful impact become clear."
Prof Davis conceded his methodology was not ideal but Ian Blanchard, professor of economic history at the University of Edinburgh and an authority on trade in Africa, said yesterday that the numbers appeared to add up.
"We are talking about statistics which are not real, all the figures are estimates. But I don't find that absolute figure of 1 million at all surprising. It makes total sense."
The arrival of gold from the Americas and the shipping of slaves from west Africa squeezed the traditional business of the Barbary merchant fleet which was transporting gold and slaves from southern to northern Africa, so they turned their gaze to Europe, said Prof Blanchard.
Slaving
However David Earle, author of The Corsairs of Malta and Barbary and The Pirate Wars, said that Prof Davis may have erred in extrapolating from 1580-1680 because that was the most intense slaving period: "His figures sound a bit dodgy and I think he may be exaggerating."
Dr Earle also cautioned that the picture was clouded by the fact the corsairs also seized non-Christian whites from eastern Europe and black people from west Africa. "I wouldn't hazard a guess about the total."
According to one estimate, 7,000 English people were abducted between 1622-1644, many of them ships' crews and passengers. But the corsairs also landed on unguarded beaches, often at night, to snatch the unwary.
Almost all the inhabitants of the village of Baltimore, in Ireland, were captured in 1631, and there were other raids in Devon and Cornwall.
Reverend Devereux Spratt recorded being captured by "Algerines" while crossing the Irish sea from Cork to England in April 1641 and in 1661 Samuel Pepys wrote about two men, Captain Mootham and Mr Dawes, who were also abducted.
Last year it was announced that one of the richest treasure wrecks found off the coast of Devon was a 16th-century Barbary ship en route to catch English slaves.
Although the black Africans enslaved and shipped to North and South America over four centuries outnumbered Prof Davis's estimates of white European taken to Africa by 12-1, it is probable they shared the same grim conditions.
"One of the things that both the public and many scholars have tended to take as given is that slavery was always racial in nature - that only blacks have been slaves. But that is not true," said the author.
In comments which may stoke controversy, he said that white slavery had been minimised or ignored because academics preferred to treat Europeans as evil colonialists rather than as victims.
While Africans laboured on sugar and cotton plantations the European slaves were put to work in quarries, building sites and galleys and endured malnutrition, disease and maltreatment.
Ruling pashas, entitled to an eighth of all captured Christians, housed them in overcrowded baths known as baños and used them for public works such as building harbours and cutting trees. They were given loaves of black bread and water.
The pasha's female captives were more likely to be regarded as hostages to be bargained for ransom but many worked as attendants in the palace harem while awaiting payment and freedom, which in some cases never came. Some slaves bought by private individuals were well treated and became companions, others were overworked and beaten.
"The most unlucky ended up stuck and forgotten out in the desert, in some sleepy town such as Suez, or in the Turkish sultan's galleys, where some slaves rowed for decades without ever setting foot on shore," said Prof Davis, whose book is published in the US by Palgrave Macmillan.
