Thralls: Viking Slaves and the Trade in People

Picture the Viking Age and you get ships, markets and farmsteads. What you almost never get is the person who ground the grain on those farmsteads, carted the manure, and slept at the animal end of the hall. Yet Viking slaves, the thralls of the Old Norse sources (þrælar), were not a footnote to that world. They worked in every household of any size, they had their own clauses in the law codes, and they were themselves cargo, moving along the same routes as furs, walrus ivory and silver. This article sets out what the evidence supports, and where it goes quiet.

One caveat shapes everything that follows. Not a single thrall left us a line of their own. Everything we have comes from the people who owned them, sold them or composed poems about them: lawmakers, saga authors, Arab travellers, Christian bishops. We are reading the owners’ side of the ledger, which means every figure, every scene and every moral judgement in these texts has to be read against the grain.

Three Sons, Three Ranks: The Picture in Rígsþula

The most famous Norse statement about slavery is not a statute but a poem. Rígsþula describes how the god Ríg, identified in its prose preface with Heimdall, visits three households in turn and fathers a child in each. The poorest hut produces Þræll, the slave; the middling farm produces Karl, the free farmer; the hall produces Jarl, the lord. The portrait is merciless. Þræll gets rough skin, thick fingers and a bent back, and his children carry mocking names such as Drumbr, “the log”, while Jarl’s offspring are given titles that ring.

The poem survives in exactly one manuscript, the fourteenth-century Codex Wormianus copy of Snorri’s Edda, and its date is disputed. Some read it as genuinely Viking Age, others as much later learned theorising. Either way it is a poor guide to how anyone lived. What it does capture, with uncomfortable precision, is how that society explained its own hierarchy: not as an outcome, but as something laid down at creation. On this logic a person born a thrall was not unlucky. They were correctly filed.

That is the trouble with these verses as history. They do not record a condition. They justify one.

Four Roads Into Bondage

There were four ways to become a thrall, and only one of them involved a raid.

The commonest was birth. A child born to an unfree mother was unfree, whoever the father was, so a prosperous farm could grow its workforce without buying anyone. The second was capture. The Irish annals record such raids with flat regularity, among them the attack of 821 on Étar, modern Howth near Dublin, which carried off a large number of women. Dublin itself, a fortified ship base from 841, grew into one of north-western Europe’s main markets for people in the tenth century.

The third road was hardship. Grágás and the Norwegian codes both contemplate a person selling themselves, or their children, during famine. The fourth was penalty: anyone who could not pay a compensation award could work off the debt in the household of the man he had wronged. Northern slavery was therefore not organised around ethnicity. It swallowed Irish, Slavs, Balts and Anglo-Saxons, and impoverished neighbours just as readily.

Laxdæla saga catches the link between raid and market in one of its sharpest scenes. Höskuldr buys a woman from an eastern trader at the Brenneyjar islands, pays three times the going rate, and takes her home to Iceland, where she turns out to be Melkorka, daughter of an Irish king. The saga is thirteenth-century literature, not a record, but the transaction had to read as ordinary or the twist would fall flat. Genetics points the same way: maternal lineages among modern Icelanders carry a strikingly high Gaelic component, far higher than the paternal lines. Part of Iceland’s settlement history is a history of abducted women.

What Viking Slaves, the Thralls, Actually Did All Day

Thrall labour was precisely the work nobody volunteered for and everybody needed done. Rígsþula lists it almost as a job description: setting fences, spreading dung, cutting peat, herding pigs, milking goats, hauling timber. Above all there was the quern, the hand mill, worked for hours every day, because without flour there was no bread and water mills stayed rare in the north.

It says something that this chore acquired its own myth. The Eddic poem Grottasöngr has King Fróði set two giant slave women, Fenja and Menja, to grind gold at the magic mill Grotti, allowing them no rest longer than a song. They respond by grinding out an army, and Fróði’s famous peace ends in blood. It is the one moment in Norse poetry where the unfree strike back, framed as a warning to owners rather than sympathy for the owned.

For women, called ambátt or þý, there was textile work on top of all this, an industry that consumed staggering quantities of labour, plus cooking, childcare and the summer shieling. And there was one more thing the sources mention without a flicker of discomfort: enslaved women were sexually available to their owners. Ibn Fadlan, who met Norse merchants on the Volga in 921 and 922, describes that as a routine feature of trading life. For how far the rest of the farming year sat from this, see our overview of everyday Viking life.

That world of hearth smoke, voyage and cargo still echoes in the music written about the Viking Age today.

From Dublin to Baghdad: The Norse Trade in People

Old Norse had a dedicated word for the business: mansal, the selling of persons. It appears in legal texts and sagas alongside every other kind of commerce, and that is the finding in itself. Trafficking was not taboo. It was a sector.

Its geography runs along three axes. In the west, captives from Ireland, Scotland and England moved through Dublin into the Norse world, on to Iceland or south towards Iberia. In the middle sat the great emporia: Hedeby on the Schleswig isthmus and Birka on Lake Mälaren, where cargo, silver and people changed hands under the same roofs. Our piece on Viking trade routes maps that network. In the east, the rivers of Rus led to Bulgar on the Volga and on into the Caliphate, where slaves from the north and eastern Europe were traded under the label saqaliba.

The silver suggests how much that eastern traffic mattered. Scandinavia and the Baltic are full of hoards of Islamic dirhams struck in the ninth and tenth centuries, and furs and wax alone cannot account for that volume. The Oxford historian Marek Jankowiak has argued that much of this silver was payment for people. The thesis is contested, but it explains the quantities better than the alternatives.

In the west the business ended earlier, under pressure from the Church. Bishop Wulfstan of Worcester preached against Bristol’s export of slaves to Ireland in the late eleventh century, and the Council of Westminster in 1102 expressly forbade selling human beings like livestock. Prohibitions of that kind always say two things at once: that the practice existed, and that it was large enough to reach a council agenda.

Property in Law: Status, Price and the Freedom Ale

In law a thrall was not a person but a possession. Kill another man’s slave and you owed no wergild to his kin, only compensation to his owner, as for a slaughtered horse. A thrall could not plead at the assembly, inherit, or bring a suit. The owner, conversely, answered for damage his slave caused: legally tidy, morally bleak.

Term	Old Norse	What it meant
Male slave	þræll	an unfree man, the householder’s property, without legal standing
Female slave	ambátt, þý	an unfree woman: grinding, weaving, milking, and sexually available
Freedman	leysingi	formally free, yet still tied to the former owner
Freedom ale	frelsisöl	the witnessed feast that made a manumission public
Slave trading	mansal	the sale of people as a recognised branch of commerce

Manumission happened, but it drew no clean line. The Norwegian Gulathing law sets out the procedure: public, before invited witnesses, and marked by a feast known as the frelsisöl, the freedom ale. Afterwards the freedman still owed service and dues to his former master, still needed his consent on important matters, and if he died childless his property reverted to the old household. Full standing within a kindred arrived only with a later generation of his descendants.

In our editorial view, that halfway stage is the most revealing part of the whole arrangement. Norse society did not treat freedom as a switch but as a ladder, and the climb took longer than a lifetime. Anyone inclined to call the Viking Age egalitarian should look here first. The assembly was the gathering of the free, and that was always a statement about who stayed outside.

What the Graves Reveal

Slaves are archaeologically elusive, because poverty leaves few objects behind and iron fetters rot away in acidic soil. The strongest evidence therefore comes not from single finds but from multiple burials in which one occupant clearly did not lie down willingly.

• Flakstad, Lofoten (Norway): multiple burials, some containing decapitated individuals. Stable isotope work by a team around Elise Naumann, published in 2014, showed these people had eaten a markedly poorer and different diet in life than the principal occupants.
• Stengade on Langeland (Denmark): a double burial in which a bound and decapitated man lay beside a far more richly equipped body, with a spear laid across them both.
• Ballateare, Isle of Man: above the grave of an armed man, Gerhard Bersu’s excavations in the 1940s found the remains of a woman with a severe skull injury, together with animal bone in the mound fill.
• The written parallel: Ibn Fadlan’s account of a funeral on the Volga in 922, at which an enslaved girl is killed and burned with her dead master. It remains the only detailed outside description of such a rite.

Caution is still warranted. A decapitated body might be an executed criminal or a prisoner of war, and the older excavations are thinly documented by modern standards. Only context, isotopes and ancient DNA together turn a suspicion into an argument that holds.

Why the Thralls Disappeared

Northern slavery did not end in an act of liberation. It ended as an accounting decision. A thrall had to be fed, clothed and supervised all year round, including the winter when a northern farm had little work to offer. A tenant sat on his own plot, carried his own risk and still handed over a share of the crop. As estates grew and rent systems grew finer, tenancy simply paid better.

The Church added its weight. It never condemned slavery outright, but it tightened the rules on trading Christians and recast manumission as a pious act. Supply dried up as neighbouring regions converted and grew harder to raid. In Iceland, references to thralls fade out across the twelfth century. Magnus the Lawmender’s Norwegian code of 1274 no longer regulates slaves, because there were none left to regulate. In Sweden, Magnus Eriksson declared at Skara in 1335 that children of Christian parents were born free.

What remains is a blank space in the middle of the popular Viking picture. The commerce that filled northern farms with silver consisted in no small part of trafficked people, and those farms ran on labour nobody gave freely. The vocabulary outlived the institution: the English word enthralled still carries the thrall inside it. Anyone telling this story should keep the chapter in, because it is not the dark exception beside the trade. It is part of the trade.