From 2012 onward, about 5,000 foreign fighters from various European countries travelled to the Levant to join the fighting. Six years later, roughly fifteen percent had died in combat. Others remained in the Middle East—imprisoned or drifting toward new conflict zones as terrorist groups lost ground. But some returned home. This wave of returnees is alarming, yet, regrettably, not unprecedented. Nearly a thousand years ago, laws were already being drafted to address the very same challenge: how a society should deal with those who come back from war.

The phenomenon of returning foreign fighters seemed to take European countries and their seasoned policymakers by surprise. Legislative reforms in criminal law were mostly reactive and improvised, as though everyone had assumed these fighters would perish on the battlefield. How could that be? Especially in countries bordering the Wadden Sea—a region with a long history of men joining foreign armies, whether driven by faith, by the lure of plunder and glory, or, more often, by a toxic mix of both.

Oh, you did not know that the Wadden Sea area is an important breeding ground for these spiritual warriors? It's essential that you finish reading this blog post.

If we set aside the Frisian mercenaries who served in the Roman Imperial Army two thousand years ago—you can read more about these fighters in our blog post Frisian Mercenaries in the Roman Army. Fighting for Honour and Glory—there were two major waves of homegrown foreign fighters. The first emerged during the Viking Age, roughly between AD 800 and 1000, and was followed by a second during the Crusading Period, roughly between AD 1100 and 1300.

In our blog post Terrorist Fighters From the Wadden Sea. The Era of the Crusades, we explore the Frisian young men who took the Cross and the destabilising effects their return may have had on medieval society. Many of these holy warriors must have returned traumatised by their experiences and, in some cases, perhaps radicalised—conditions for which medieval society had neither the concepts nor the vocabulary we use today, such as PTSD and radicalisation.

In this blog post, we will zoom in on the return of Frisian fighters who took part in ransacking Viking warbands, how the process of homecoming for these individuals was a social reality, and how their reintegration into society was regulated. We will illustrate that both the north of Germany and the Netherlands have a lengthy legal tradition of about a thousand years on how to deal with these homecoming, blood-and-booty-thirsty troublemakers.

At the same time, it is worth remembering that Frisians did not only participate in Viking raids; they also served in Anglo-Saxon naval fleets fighting against those very same Vikings. In AD 897, no fewer than sixty-two Frisians and Englishmen died in battle while serving in King Alfred’s army against the Danes—that is, the Vikings. Sing along with our blog post ♪ They Want You as a New Recruit ♪ to discover more about this fascinating episode in English-Frisian history during the Early Middle Ages.

It is difficult to estimate how many men—and women?—from Frisia begav seg på farten (‘went on the move’) and took part in Viking raids across Europe and beyond. The Frisians, however, were far from unique in this respect. Other peoples and tribes also joined the Norsemen in their raiding expeditions. Even so, the number of Frisians who ploughed through the foaming waves alongside the Northmen may have been considerable.

One indication comes from the year AD 855, when an army of pagans, described in the Annales Lindisfarnenses as Dani et Frisones (‘Danes and Frisians’), landed on the island of Sheppey in the mouth of the River Thames in England. Danes and Frisians, of course, were neighbours, separated only by the Wadden Sea and the North Sea. Another clue comes from archaeological excavations on Île de Ré, off the western coast of France, where Viking remains have been uncovered, pointing to the possible presence of Frisian participants as well (Bolle, Ciesielski & Torchut 2025). By the way, Île de Ré is a tidal marshland environment that Frisians were very familiar with; it is almost the sea, except that the water has turned into marsh, but for the rest, it is just as salty and barren as the sea.

Furthermore, only a few years after the attack on the island, warlord Ubbe the Frisian departed with his army of Scaldingi—‘Scheldt men’—from the estuary of the River Scheldt, an area that still belonged to West Frisia at the time, to invade England. Also known in Danish as Ubbi fríski, Ubbe is regarded as one of the three founding commanders of the legendary and fearsome Great Heathen Army. This same Ubbe is said to have led, together with the leaders Inguar and Halfdan, the raid on the island of Sheppey.

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The Nationality of Ubbe the Frisian — Often it is assumed that Ubbe is Danish since he is a son of Ragnarr Loðbrók according to legends. Part of the Loðbrók legend is that Ubbe had a Frisian mother. However, we can safely assume Ragnarr was non-historical (IJssennagger 2017), which makes Ragnarr irrelevant for proof concerning Ubbe's 'nationality'.

The name Ubbe is still a Frisian first name today and derives from the first name Obe. Old Frisian legends mention a third prince of Frisia named Ubbo I, who supposedly ruled Frisia between 151 and 71 BC and was a grandson of Prince Friso, the legendary founder of Frisia. According to the same non-historical traditions, Ubbo I also founded the city of Cologne. The fourth duke of Frisia was said to be Ubbo II, who supposedly ruled from AD 240 to 299. Another Ubbo appears in the historical record as the high-medieval local ruler Ubbo Habbena from Aurich in the region of Ostfriesland.

In other words, there is certainly no shortage of Ubbes and Ubbos in the province of Friesland and the region of Ostfriesland. Nevertheless, as Van der Tuuk (2025) points out, Ubbi was also a common Scandinavian name during the Middle Ages. And, of course, old legends and sagas cannot by themselves serve as proof of a Frisian origin.

Some scholars suggest that the name Ubbe or Ubba is, in fact, Old Norse and derives from Úlfr, with the loss of the initial consonant. According to this theory, Ubbe and the Viking warlord Rodulf (Rod Ulf, meaning ‘praise wolf’) were one and the same person, and Ubbe was born and raised on the island of Walcheren in West Frisia (Lewis 2018).

To complicate matters further, at the mouth of the River Old Rhine stood the Early Medieval Frisian settlement of Hrothaluashem, or ‘Rodulfsheim’, meaning ‘house of Rodulf.’ Today, this place is known as Rijnsburg in the province of Zuid Holland. Hrothaluashem is considered part of an Early Medieval elite central-place-complex (CPC), a type of site also found in southern Scandinavia. For more background on CPCs, see our blog post Tolkien Pleaded in Favour of King Finn. An Immortalized Royal Tragedy. And if wolf names pique your interest, have a look at Who’s Afraid of Voracious Woolf?—The Dread Beast is Back.

The identification of Ubbe and Rodulf as one and the same person, however, is strongly disputed by others (Van der Tuuk 2025).

Or, should we keep it simple?

Firstly, as stated, Ubbe is a typical Frisian first name. Secondly, Ubbe was not known as ‘the Frisian’ without reason. Thirdly, he did not command the Scaldingi—that is, warriors from the River Scheldt in western Frisia—without reason either. His name, recorded around AD 1100 in the Annales Lindisfarnenses et Cantuarienses, is given as Ubba dux Fresonum, meaning ‘leader of the Frisians’, not the Danes. Fourthly, foreigners and other non-Scandinavians participating in Viking raids were by no means unusual.

So, the conclusion seems straightforward: Ubbe was a Frisian. And who knows? The distinction between raiding Frisians and Danes may have been a fluid one, with Ubbe perhaps being a typical example of this overlap. But rather than simply defending the Frisian interpretation, let us turn the question around: what arguments are there for considering Ubbe Scandinavian?

That 'to viking' was also a job description, rather than simply an ethnic designation for Scandinavians, is supported by recent genetic research (Margaryan 2020). Genetic samples from Viking burials stretching from the British Isles to Italy, Russia, and Ukraine show that individuals buried as Vikings were sometimes local inhabitants or otherwise non-Scandinavian. In a few cases, even so-called Viking warriors buried in Scandinavia turned out to have been Sámi.

Unfortunately, for reasons that remain unclear, this recent research did not include ancient DNA samples from the neighbouring southern North Sea coast—that is, Frisia. Perhaps the samples were simply too close at hand and overlooked? Despite the historic sources, discussed in this blog post, of Frisians participating in these raids.

In Yorkshire, in the north of England, there is a place called Frizinghall, meaning ‘hall of the Frisians’. The name is believed to derive from Frisian settlers (Hines 2001, Bremmer 2005). Naturally, we like to speculate that this might have been where Ubbe had his hall. Frizinghall is one of around twenty English place names whose etymology can be linked to Frisian settlers. Moreover, most of these place names are located within the former Danelaw, offering a clue to the period in which Frisians settled in the region.

Could some of these Frisian settlers have earned their living as Vikings as well? See our blog post Have a Frisians Cocktail! A Rich Composition to learn more about Frisian place names in Britain.

If interested to know more about this chap Ubbe and his Great Heathen Army see—only during—daylight, our blog post Walcheren Island. Once the Sodom and Gomorrah of the North Sea.

For now, we leave all the sea fog surrounding Ubbe behind us and return to political Frisia.

Early-medieval Frisia encompassed the lands, islands, and waters stretching from the mouth of the River Scheldt in the southwest of the present-day Netherlands to the mouth of the River Weser in the northwest of Germany. Farther north along the Wadden Sea coast, bordering the lands of the Danes and the Jutes, Frisians also settled during the Early Middle Ages, in a region that would later become known as Nordfriesland. The coastline stretched for hundreds of kilometres, comprising sandy, muddy, and peaty terrain that was difficult to traverse. Geographically, this coastline occupied a central position between the Dena lagunema (‘Danelaw’) in the British Isles to the west, and Denmark, as well as southern Norway and Sweden, to the east and northeast.

The influence of the Vikings in what is now the Netherlands, whether or not these territories remained under the ultimate authority of the Frankish kingdoms, was very direct. During the ninth century AD, Viking warlords such as the renowned Rorik of Dorestad, Hemming Halfdánsson, Rodulf, Harald Klak, and Godfrid the Sea-King ruled large parts of medieval Frisia. These territories included the Central Riverlands, home to Dorestad, the most lucrative trading emporium in north-western Europe; the coastal zone along the North Sea known as Kinhem or Kinnlimasiða in Old Norse, corresponding to the present-day region of Kennemerland in the province of Noord Holland; and the estuary of the River Scheldt, including the island of Walcheren in the province of Zeeland.

For more background on these Danish warlords and their rule over (West) Frisia, see our blog post The Abbey of Egmond and the Rise of the Gerulfing Dynasty.

Besides West Frisia and Mid Frisia, East Frisia—the modern region of Ostfriesland—was also ruled by a Danish warlord. In a way, East and Mid Frisia were regarded by the Danes as their outer provinces. Twelfth-century AD sources report that, following a Danish military campaign in Frisia in AD 810, the Danish king received an annual tribute of 10–30 marks of silver from his Frisian possessions. This was, in fact, a relatively modest and respectable tax, comparable to the levies imposed on other ‘outer’ provinces (Sindbæk 2011).

From AD 826 onward, it was the Viking earl and warlord Harald Klak Halfdansson, brother of Halfdane Hemming—who died in battle on the island of Walcheren in AD 837—who ruled on behalf of the Franks over the pagus, or ‘territory,’ of Rüstringen in north-western Germany. From there, he controlled the mouths of the Weser and Jade rivers. The great Battle of Norditi, fought in the Norderland area of Ostfriesland in AD 884, was likewise a consequence of the (semi-)permanent presence of Norsemen. The battle was won by the Frisians and Franks and, according to the old records, cost the lives of a staggering 10,377 Vikings. See our blog post A Theel-Acht. What a Great Idea! to learn more about this remarkable battle.

Long-term presence of Norsemen in Frisia is also presumed on the (former) Wadden Sea islands of Texel, Wieringen, and Huisduinen, located in the north of the province of Noord Holland in the northwest of the country. More about the Viking presence on the former island of Wieringen will be discussed further below.

The former island of Huisduinen lay close to the (former) island of Wieringen, which has been incorporated into the polders and forms part of the coastline. Huisduinen was known as Husidina in the eleventh century AD, indeed meaning 'house-dunes' (Van Berkel & Samplonius 2018). Today, Huisduinen is the name of a small village with a lighthouse named Lange Jaap ('tall Jacob'). Sand dredged from off the coast contained a Viking sword, a silver armlet with five rings attached to it, and English and Arabic coins, which are leads pointing to Viking presence on Huisduinen, as on Wieringen (Roos 2011).

As for the (semi-)permanent presence of Vikings in Frisia, a fascinating example can be found in the ninth-century AD Annales Fuldenses: the account tells of a Norseman living among the Frisians who came to their aid when a Viking raiding party attacked his adopted homeland. Read the full story in our blog post Frisia, a Viking Graveyard.

The presence of the aforementioned Ubba the Frisian, and notably the Scaldingi mentioned in connection with him, in the area of the modern province of Zeeland is also relevant in this context. Finally, the distribution of so-called imitation gold solidi—coins that imitate late Roman gold coinage—provides another indication of the (semi-)permanent presence of Vikings in Frisia, particularly in what are now the provinces of Friesland and Groningen. These coins were probably minted by Vikings rather than by Frisians, as was previously assumed (Coupland 2016).

The Frisian and Danish seafaring peoples were also culturally connected. While parts of Frisia had only recently been converted to Christianity, Frisians had shared the same heathen beliefs as their northern cousins for centuries, and some may even have identified with the Norsemen. Although the Franks had incorporated most of Frisia into their kingdoms during the eighth century AD, and despite the efforts of Irish, Scottish, and Anglo-Saxon missionaries—including monks from the monastery of Rath Melsigi in Ireland—to Christianize the region, the Frisians living on the outer fringes of their homeland may not have been fully pacified and were certainly not all baptized during the Early Middle Ages.

For example, Frisians continued to wear so-called Kievan Rus crosses — a hybrid of Christian and heathen designs — well into the eleventh century AD, much like the Vikings of southern Scandinavia (Visser 2025).

In addition, both Scandinavians and Frisians were heavily involved in the rich supra-regional trade for a long time. Throughout southern Scandinavia, important trading ports, Frisian trade colonies, and Frisian guilds have been established. To get an idea of the huge scale of Frisian free trade, see our blog post Porcupines Bore U.S. Bucks. The Birth of Economic Liberalism.

The Frisians, therefore, initially kept interacting with their pagan neighbours as ever before.

But eventually, Frisian beliefs and culture turned away from the grim north, and the Frisians became remarkably devout Christians, covering their lands with churches and monasteries on a scale unparalleled anywhere else in Europe.

All Frisians once belonged to the north over the sea to the terrible corner and all were heathen, who were Frisians (Old Frisian Emsinger Law). (transl. by IJssennagger)

These texts date from the High Middle Ages. By then, the Frisians were a people who had recently shifted their allegiance from the heathen, supposedly barbaric north to the Christian, supposedly civilized south. This change is symbolized by the tribute or tax they were required to pay: the clipskelde gave way to the huslotha. The clipskelde was the tribute paid to the Norsemen—that is, the Danes—in return for loyalty to an overlord. The huslotha, by contrast, was a tribute paid to the Franks.

The word clipskelde is composed of the Old Frisian clippa or klippa, meaning ‘to clink’, and skelde, meaning ‘debt’—literally, therefore, a ‘clinking debt’. Old Frisian law stipulated that the pennies to be paid had to be so heavy that ma him moeghe hera clinna in ene lewen wr nioghen fecke huses (‘one can hear them clink in a scale over a distance of nine house lots’). The word huslotha, meanwhile, consists of hus, meaning ‘house’, and lotha. The meaning of the latter is uncertain; it may have meant ‘part’ or referred to a lot or plot of land.

That we Frisians subjected ourselves to the south and clipskelde [tribute] refused and became subordinate and obedient to the southern king, regarding all rightful tenths [kind of tax] and paid huslotha [house tax], according to the asega’s [law expert] judgement and according to the people’s land-law, because we belonged to [king] Redbad the unpeaceful-man, all that was Frisian. (transl. by IJssennagger)

For more on the huslotha and clipskelde taxes, study our blog post With a Noose Through the Norsemen’s Door.

Treatment of Frisians disembarked from longships

Participation of the Frisians in the Viking warbands could be voluntary or involuntary. During raids, the noerdtscha diuelen (Old Frisian for 'northern devils') could take captives—sometimes young children and sometimes adults. These captives could be sold as slaves back home or somewhere else for a fair price. Alternatively, they could be bought free by their relatives, which still meant a profit for the cunning Vikings. Lastly, captives could be forced to participate in plundering, killing, and raping during raids. This blog post focuses on these aspects.

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Saga of the Headstrong Frisian — Set during the Viking Age, this saga tells the story of a North Frisian from the Wadden Sea island of Balkum, in Nordfriesland. The island lay west of Föhr. A headstrong and heathen Frisian, he took part in Viking raids. One day, when he returned from yet another raiding expedition, he found that his island had been swallowed by the sea. That alone was a devastating blow. But worse still, in his absence, all his kin and friends had been converted to Christianity by the Roman Catholic Church. It was more than he could bear. From the sacrificial stone that once stood on Balkum, he cast himself into the sea and drowned.

Quite the theatrical bunch, those Frisians of old.

Some captives managed to escape from the Danes, while others were later ransomed and set free. They then returned to their humble villages and family holdings in Frisia. The number of returning warriors was apparently significant enough to warrant legal regulation—a striking indication that Frisians themselves frequently served aboard Viking longships, unless, of course, the Frisians simply had a penchant for making laws, even when there was little societal need for them.

The Old Frisian codices, or law books, of the fourteenth and fifteenth centuries AD still contained articles and clauses concerning Frisians returning from Viking captivity. Some of these legal compilations had been built up over several centuries, with layers of law traceable to around AD 1000 (IJssennagger 2017). The medieval Old Frisian law books preserve several terms for a Viking, including witzing, witzeng, wising, and witzend, which are related to the Old English wicing, meaning 'pirate.' Interestingly, the origin of the word Saxon likewise carries the meaning of 'pirate' (Springer 2003). See our blog post, Have a Frisians Cocktail! A Rich Composition, for more on the origin of the term Saxon. Thus, Viking and Saxon may originally have functioned more as terms denoting a profession or occupation, rather than as names for a particular people or tribe.

Another etymological explanation derives Viking from the Old Swedish verb vika or Old Norse vikja, meaning 'to give way' or 'to change places.' The term has been compared with the modern Mid Frisian verb wykje, 'to give way.' In this interpretation, the original sense may have referred specifically to the practice of giving up one’s place on a rowing bench to a rested rower. Thus, vika and to viking could be understood as referring to a sea voyage in which rowers regularly changed places (Heide 2005).

Below are the clauses of two law books concerning the return of Frisian fighters, namely the Fivelgo Manuscript and the First Rüstringer Codex. Fivelgo is a former pagus 'district' in the present-day province of Groningen in the Netherlands, and Rüstringen is a former pagus in the present-day region Ostfriesland in Germany. The First Rüstringer Codex, or R1 in the jargon of historians, dates from ca. AD 1300. The Fivelgo Manuscript, or F in the same jargon, dates from ca. AD 1450. Both texts concern the Twenty-four Land Laws.

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Rüstringen Text — Thit is thet twintegoste londriucht: Sa hwersa Northman an thet lond hlapath, and hia enne mon fath and bindath and ut of londe ledath, and eft withir to londe brangath and hini therto thwingath, thet hi hus barne and wif nedgie and man sle and goishus barne and hwetsa hi to lethe dwa mi, alsa hi thenne vndfliuch ieftha lesed werth, and withir to londe kumth and to liodon sinon, and hi mugi bikanna brother and swester and londethele and erue and sinera aldera hof and hus, sa fari hi oua sin ein erue uter liodskelde. Sa willath him tha liode thing toseka and sinne opawerpa thruch thet grate morth, ther hi er mith tha witsingon efremid heth. Sa mire thenna afara thene warf gunga and iechta mire tella; enne eth hach hi thenne opa tha heligon to swerande, thet hit al debe bi there need, alsa him sin hera bad, ther hi was liues and lethana en vnweldich mon. Sa ne thuruon him tha liode ne frana tohalda seka ni sinna, thruch thet thi frana ne machte thes fretha waria; thi skalk skolde dwa, alsa him sin hera bad, thrum thes liues willa.

This is the twentieth land law: When the Norsemen invade the land and they take a man captive and bind him and carry him off abroad and later take him back in the land and force him to burn down houses and rape women and kill men and burn down churches and whatever sort of evil he may do, and if he flees or is released and he comes back to his land and to his folk, and he recognizes his brother and sister and family estate and ground and his parents’ court and house, then he can take back his own land without payment to the folk. When his people want to charge him and accuse him of a crime because of the great murdering that he had committed with the Vikings. Then he may come before the assembly and plead guilty and confess; then he must swear on the relics that he had done everything because he was forced by his lord against whom he could not voluntarily decide over his body or life. Then neither the people nor the frana (*) can charge him as guilty or with crime, because the frana cannot secure his peace; the servant had to do what his master ordered, for his life’s sake. (trans;. by IJssennagger)

(*) The frana was a functionary originally who acted on secular matters on behalf of the bishop. Task of the frana was to guarantee the peace and execute legal rulings. For this the frana had the monopoly for violent action against disobedient. It was his duty to execute the legal rulings. Originally, the frana, together with the asega (literally meaning 'law saying', a legal expert and priest combined and the one guiding the trial) led the process of the law thing. Frisians happen to have a notable history concerning the thing gatherings. See our blog post Well, the Thing Is... Speaking From the Moral High Ground of Old.

Fivelgo Text — Thet twinthechgiste londriucht is: jefter Northmon kumath and anne mon hendat and bunden to tha skipe brengat and hi mith himman in sine ayna londe to ene thorpe kumpt an hi ther hus barnt ande wif a need nimth ande mon slaith en hwet sa hi to ewela decht, jef hi thenna vunfliucht jefta leszed wert, sa stant hi an liudworpena ware an on tha bonnena thinge; and sprecht ma him to, thet hi alle ewela deda den hebbe, sa iecht hi the salles and queth, hi hebbe alsa den; end hi ne thor ther nen bote vmbe iewa and ac nanne frethe felle, hwant hi dede tha hwile, alsa hi en skalc was; thi schalc scolded wan, alsa him sin hera bad, thruch thes liwes willa.

The twentieth land law is: when Norsemen come and take a man captive and bring him tied up to their ships and with them he comes back in his own land in a village and he burns houses and rapes women and kills men and whatever evil he does, then he appears, when he escapes or is bought free, before a yard gathered by the people and in the banned thing (*); when he is accused for doing all these evil deeds, then he confesses all and says he has done that; and he neither needs to pay a fine nor to pay for the peace, because he did it, when he was a servant; the servant must do what his lord commands to save his life. (transl. by IJssennagger)

(*) A thing—or ting or ding—was a governing assembly of northern Germanic societies of which Frisia was part. The parliament in Iceland still is named Alþing. Frisians happen to have a notable history concerning the thing gatherings. See our blog post Well, the Thing Is... Speaking From the Moral High Ground of Old.

Strikingly, the two texts are remarkably similar, despite more than a century separating them. At their core, both address the same social and legal question: who was entitled to the property of men taken captive by Vikings? Upon their return, these men could reclaim their former family property and lands, but only under certain conditions.

The first condition was that they had to prove themselves the rightful owners by identifying their family and recognizing their family estate and possessions—a practical solution in a society without passports, land registries, or any central register of citizens. The second condition was that they had to make their claim within a prescribed period. The particular clauses mentioned above contain no fatal deadline, but other Old Frisian sources indicate that thirty years was a common limitation period. So there was, apparently, no great hurry to return.

The third condition was rather more serious. If, during their time abroad, they had taken part in fighting, killing, burning houses, raping women, or other such acts within Frisia, they had to make it plausible that they had done so in order to save their own lives. In other words, they had to demonstrate that they had acted under duress—that they had been forced to commit atrocities against their own people.

If all three conditions were met, they could reclaim their property without paying compensation or a fine to anyone and resume their place among their neighbours. They could even greet them again across the fence in the morning—provided, of course, that they had not happened to kill that particular neighbour during one of their raids.

But what happened if a returning warrior had killed and raped his own people of his own free will, rather than under duress? We find an answer in the Old Frisian Hunsinger codices from the fourteenth century AD. The passage does not concern Viking warbands, but men who had joined the Saxon forces “with the high helmets” and fought against their own country, Frisia. The verdict was clear: they were regarded as traitors.

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Hunsinger Recht Text — En vrrede and hi wrreth lond and liude and hi fart inur Saxenna merka and hi uthlath thene haga helm and thene rada skeld and thene sareda riddere and hi binna Fresena merkum man sleith and burga barnd, sa ach ma hine north inna thet hef to ferane and theron te sansane.

A traitor to the land and he betrays land and people and goes into the border region of the Saxons and gets from there the high helmet and the red shield and the armed knight and he goes into the land of the Frisians and kills men and burns strongholds, then he should be taken northwards to the sea and be thrown in the sea. (transl. by IJssennagger)

The phrase “to be taken north and thrown into the sea” certainly did not mean going for a refreshing swim on the North Sea coast or taking a leisurely stroll across the mudflats of the Wadden Sea. No—it meant being drowned. And things could get considerably worse. If you had violated a religious sanctuary, you might first be castrated and have your ears slit before being tied to a pole and left there as the tide went out. Then you simply had to wait for the flood to return.

Under modern law of the Netherlands, the foreign fighter, or traitor in medieval language, is no longer stripped of his life, testicles, ears, and so forth, but of his Dutch nationality instead. One might argue that the punishment has thus shifted from something brutally tangible to something rather more abstract—and, perhaps, fictional.

There is another detail worth noticing: the compass point is north. That is where heathendom lies, where the Devil lives—the pagan world from which the Frisians were supposedly liberated by the Christian Franks and Anglo-Saxon missionaries.

Be that as it may, the keen reader may already have noticed that whether returning foreign fighters had been killing, plundering, or raping people outside the territory of Frisia was entirely irrelevant to their right to reclaim their property—or to any corrective punishment imposed upon their return. Such acts were not considered treason either. Indeed, there was no such thing as international criminal law applicable to their actions abroad.

Ironically, former West Frisia is now proud to host the Capital of International Law: the city of The Hague, home to a remarkable concentration of international courts and tribunals. Their authority is such that even when an international court declares, for example, a state's military action or occupation illegal, the state concerned will at least go to the trouble of responding to the court—usually to explain why it will not abide by the verdict. But that is another story.

Since Frisia was still a feud society, another route to reclaiming one’s possessions may also have been available. A foreign fighter who had killed, plundered, or committed similar acts against his own people within Frisia, without having been forced to do so by a master, might have been able to settle the matter by compensating the victim’s family and relatives with a monetary payment, together with a possible additional fine intended to restore the broken peace. Once these fines—or weregild (see below)—had been paid, the matter could be considered settled and forgotten, allowing the individual to reclaim his former property.

To give the reader an idea of the sums involved in such fines or blood money, consider the following:

If someone killed another person, the killer was required to pay a weregild, or wergeld—literally, 'man price.' In the case of a freeman, the weregild amounted to 1,664 grams of fine silver. Remarkably, this silver equivalent remained more or less stable, despite the various monetary systems and conversions used in the legal texts over the centuries, involving currencies and units such as the dinar, solidus, sceat, mark, and pound. In other words, the nominal currency changed, but the underlying quantity of silver remained remarkably constant throughout the Middle Ages.

Converted into today’s money, 1,664 grams of silver would have been worth approximately US$1,930 at the silver price in June 2025. That may sound surprisingly modest by modern standards, but in medieval terms it represented roughly six or seven years’ worth of living expenses.

If you want to delve deeper into how weregild actually functioned—and you probably should—see our blog post You Killed a Man? That’ll Be 1 Weregeld, Please. No economics degree required.

Research has also been conducted into the fines that are still practiced among the Kamba people in the Mashariki region of Kenya (Willemsen 2014). There, the weregild for killing a man amounts to fourteen cows and one bull; for a woman, it is seven cows and one bull.

And, to answer the question you are probably asking: in Frisia—and likewise in East Anglia—the weregild for a woman was the same as that for a man of the same social status. This was not the case among all Germanic peoples. In many other Germanic societies, a woman’s weregild was higher, sometimes as much as three times that of a man’s, particularly if she was of childbearing age.

One of the Viking hoards found in Frisia, on the former Wadden Sea island of Wieringen in the province of Noord Holland, contains 1,663 grams of silver—remarkably close to the approximately 1,664 grams of fine silver that constituted a weregild. The so-called Westerklief I hoard, dated to around AD 850, consists largely of complete silver ornaments and heavy, unfragmented silver ingots.

Was it a weregild after all, or is the resemblance merely a coincidence? And if it was indeed a weregild, what was a northeska wigandum—a 'northern fighter' in Old Frisian, denoting a Viking—doing with a weregild in Frisian territory? We simply do not know. Perhaps it was a payment he had received; perhaps it was a payment he was preparing to make; or perhaps it was a payment made to free a Frisian captive who would be forced to join the longships. Create your own story!

Besides the Westerklief I silver hoard, dated to around AD 850, a second hoard was discovered on the very same plot of land on Wieringen: the Westerklief II hoard. This smaller hoard, containing approximately 0.5 kilograms of silver, dates to around AD 876 and consists mainly of hacksilver. Unlike Westerklief I, which contains virtually no Arabic coins, Westerklief II is dominated by Arabic silver coins, most of them originating from what is now southern Iraq. Like its larger counterpart, Westerklief II is considered a Viking-period hoard (Besteman 2009). And yes, we said Iraq.

As a side note, if the reader thought hacksilver was somehow an exclusively Viking phenomenon, think again. Its use goes back much further. The Romans, for instance, are known to have bought the allegiance of Germanic tribes with hacksilver. A hoard discovered near the town of Echt, in the province of Limburg, and dated to around AD 411, provides a striking example (Wijnendaele 2024).

As a little bonus, there is this: the name Wieringen derives from Wirense, the name by which the island was already known in the ninth century AD. It is generally understood as meaning 'land of wiers,' with the element wier referring to an elevated height. The gently rolling landscape of Wieringen is, in fact, the remnant of a push moraine formed during the last Ice Age. A related word is wierde, used in the province of Groningen for a terp or artificial dwelling mound (Van Berkel & Samplonius 2018).

Note 1 — The raids of the Vikings are often the focus when we talk about raiding in northern Europe. In fact, the wider North Sea had a long-standing tradition of piracy. During the first five centuries of the Common Era, piracy was widespread and extended from the southern coast of the North Sea to Britannia, Brittany, and all the way to the Mediterranean. See our blog post Our Civilization—It All Began with Piracy.

Note 2 — Quite a number of Vikings have found Walhalla on Frisia territory in the ninth century. Do a body count reading our blog post Frisia, a Viking Graveyard. We counted 11,180 deaths. No, not mistakenly one 1 too many!

Note 3 — The Senja Neck-Ring Runes

Up in the high north of Norway at the small village of Senja, a beautiful silver neck-ring has been found dating mid-eleventh century. The neck-ring is being kept at the Norges arktiske universitetsmuseum in Tromsø. Onto both ends of the clasp runes have been carved. It is a half stanza of four lines. It goes as follows:

Fórum drengja Fríslands á vit ok vígsfǫtum vér skiptum

Different translations are possible. At first the inscription was translated as:

• We went to visit the young lads of Frisia and we it was who split the spoils of war (Page 1987, Van der Tuuk 2015), or

• We went to meet the valiant men of Frisia and we divided the spoils of the fight (Riksantikvarieämbetet website)

More recently it has been translated as follows:

• We went to visit young Frisian warriors and divided up the war-gear (Barnes 2012), or

• We went to visit young Frisian trading partners and exchanged war-gear (Barnes 2012)

So, either it was Vikings who raided Frisia halfway the eleventh century (which is a bit too late because by that time no documented raids on Frisia have taken place anymore) and after they divided up the booty, or Vikings and Frisians went raiding together and divided up the booty, or Vikings traded with Frisian merchants and divided war-gear.

Note 4 — If interested in an overview of the documented attacks of the Northmen in Frisia, check the science-debunking website of Gjallar—Aanvallen in de Lage Landen ('attacks in the Low Countries').

Note 5 — Featured image by Jørn Løvland.

Suggested music

Eric & the Vikings, Time Don't Wait (1972)

Further reading

Algemene Inlichtingen- en Veiligheidsdienst (AIVD), Uitreizigers en terugkeerders (website)

Barnes, M.P., Runes. A handbook (2012)

Besteman, J., A second Viking hoard from Wieringen: Westerklief II (2009)

Berkel, van F. & Samplonius, K., Nederlandse plaatsnamen verklaard. Reeks Nederlandse plaatsnamen deel 12 (2018)

Bremmer, R.H., Frisians in Anglo-Saxon England: A historical and toponymical investigation (2005)

Bremmer, R.H., Hir is eskriven. Lezen en schrijven in de Friese landen rond 1300 (2004)

Bolle, A., Ciesielski, E. & Torchut, J.S., Des tombes inattendues à l’île de Ré témoignent d’échanges avec le monde nordique (2025)

Bos-van der Heide, H.S.E., Het Rudolfsboek (1937)

Coupland, S., Recent Finds of Imitation Gold Solidi in the Netherlands, The Numismatic Chronicle 176 (2016)

Engelkes, G.G., Der schwarze Rolf (1936)

Finlay, A. cs (ed.), Saga-Book Vol. XL (2016)

Halink, S., “Almost Like Family. Or Were They?” Vikings, Frisian Identity, and the Nordification of the Past (2022)

Heide, E., Viking – ‘Rower shifting?’ An etymological contribution (2005)

Henstra, D.J., The evolution of the money standard in medieval Frisia. A treatise on the history of the systems of money of account in the former Frisia (c. 600 – c.1500) (1999)

IJssennagger, N.L., Between the Frankish and the Vikings: Frisia and the Frisians in the Viking Age (2017)

Hilder, M., The Last Kingdom: Ubbe (2023)

Hines, J., The Role of the Frisians during the Settlement of the British Isles (2001)

IJssennagger, N.L., Central because Liminal. Frisia in a Viking Age North Sea World (2017)

Jacobs, T.J.M., Friese vosten (2020)

Klæsøe, I.S. (ed.), Viking Trade and Settlement in Continental Western Europe (2010)

Lewis, S.M., Rodulf and Ubba. In search of the Frisian-Danish Viking (2018)

Margaryan, A, et al, Population genomics of the Viking world (2020)

Meertens Instituut, Corpus of First Names in The Netherlands, Nederlandse voornamen (website)

Nieuwenhuijsen, K., Lex Frisionum. Inleiding (2010)

Nijdam, H., Klinkende munten en klinkende botsplinters in Oudfriese rechtsteksten: continuïteit, discontinuïteit, intertekstualiteit (2009)

Nijdam, H., Lichaam, eer en recht in middeleeuws Friesland. Een studie naar de Oudfriese boeteregisters (2008)

Nederlands Omroep Stichting (NOS), Twaalf Nederlandse IS-vrouwen en hun 28 kinderen opgehaald uit Syrië (2022)

Page, R.I., Runes. Reading the past (1987)

Riksantikvarieämbetet, Runor (website)

Roos, R. (ed.), Duinen en mensen. Noordkop en Zwanenwater (2011)

Schoorstra, W., Erfskip. De saga fan Ubba Skylding (2023)

Siems, H., Studien zur Lex Frisionum (1980)

Sindbæk, S., Silver Economies and Social Ties: Long-Distance Interaction, Long-Term Investments – and why the Viking Age happened (2011)

Sinn, A.T., Der Exot von Hattstedt. Auf den Spuren eines besonderen Sondenfundes (2019)

Stoter, M. & Spiekhout, D. (eds.), Wij Vikingen. Friezen en Vikingen in het kustgebied van de Lage Landen (2019)

Tuuk, van der L., De Friezen. De vroegste geschiedenis van het Nederlands kustgebied (2013)

Tuuk, van der L., Ubbi de Fries. Scheldevikingen in het grote heidense leger (2025)

Tuuk, van der L., Vikingen. Noormannen in de Lage Landen (2015)

Tuuk, van der L. & Mijderwijk, L., De Middeleeuwers. Mannen en vrouwen uit de Lage Landen, 450-900 (2020)

Vinkenoog, H., Frisians in the Great Heathen Army (2020)

Visser, A., Kruishangers uit het Kievse Rijk (2025)

Vries, O., Asega, is het dingtijd? De hoogtepunten van de Oudfriese tekstoverlevering (2007)

Vries, O., De taal van recht en vrijheid. Studies over middeleeuws Friesland (2012)

Vries, O., De wylde Wytsing (2019)

Willemsen, A., Gouden Middeleeuwen. Nederland in de Merovingische wereld, 400 – 700 na Chr. (2014)

Wetenschappelijk Onderzoeks- en Documentatie Centrum (WODC), Justitiële verkenningen. Terugkeer en re-integratie van ex-Syriëgangers (2022)

Wijnendaele, J.W.P., De wereld van Clovis. De val van Rome en de geboorte van het Westen (2024)