Sea of the Vikings

Ole Jørgen Nørgaard.

The Vikings traveled far and wide on their ships. To the west they sailed to England, Ireland, the Faroe Islands, the Shetland Islands, the Hebrides, Iceland, Greenland and America. To the south they came to present-day Holland, Belgium, Germany, France, Spain and northern Italy. Eastward sailed across the Baltic Sea and came to the lands south of it. They sailed up the rivers of Russia and founded the trading city of Novgorod and the Kievan dynasty. They came to the Black Sea with Constantinople and to the Caspian Sea. Wherever they went, they made a name for themselves.

Ireland
Ireland was already Christian in the years after the year 431 when St. Patric came to Ireland and founded a monastery there, which spread Christianity to England and mainland Europe. At the time, Ireland was divided into 135 different kingdoms that fought each other fiercely. This made Ireland a grab-and-go table for the Norwegian Vikings in particular, who used the situation to found Ireland's later capital, Dublin, in the year 841, and set up a slave market there, which quickly became Europe's largest. In particular, the Irish women from there were famous for their beauty and in high demand.

England
When the Vikings started coming in the 8th century, England was divided into about 5 large kingships or earldoms (Wessex, East Angelia, Cumbria, North Humbria and Mercia, which was the largest).

To cut a long story short.
After a dress rehearsal in 789 in which a group of Vikings went ashore and murdered the harbormaster and his people in Portland, the nine-eleven of the Viking Age came on June 8, 793: Directly across the open sea from the Oslofjord, the Vikings came and landed on the holy island of Lindisfarne for the coast of Northern England. They plundered the rich monastery there, burned it down, drowned some monks, killed others, and carried off still others. Then they sailed home with the monastery's valuables. The monastery had also become rich by writing and selling gold-inlaid books.This attack then attracted the same attention in the civilized world as the attack on the World Trade Center 9/11 2001 did in the civilized world of our time. Therefore, it has since been considered the event that ushered in the Viking Age. Until now, God and every man had believed that such a long trip across the open sea was impossible. It wasn't, and there were more to come. 

Just a short account of the Vikings' activities in England over approx. 250 years would fill a book, only need be mentioned: The Vikings ravaged England every year. Often they were paid to leave without looting. The funds that came in from here were largely used to finance new raids. The great pagan army of Vikings that had ravaged and plundered France since the year 850 came in 865 to England and began to plunder and form principalities there. Many Danes settled in the then Danish Danalagen in England.

In 1002, the English king, Edward the Wise, ordered all Danes killed on November 12-13. The mass murder triggered violent revenge reactions from Denmark in particular and eventually resulted in the Danish Viking king, Svend Tveskæg, conquering England in 1012. The expedition was financed by the English themselves with the Danish debt they had paid to the Vikings earlier. Svend Tveskæg died suddenly in 1014 and his young son, Knud, aged approx. 18 years, was driven from England, but returned and conquered England once more. Knud was now king in both England, Denmark and Norway. He had thus become one of the two most powerful men in Christendom!

After participating in the coronation of the German-Roman Emperor (Conrad II) in 1027 in St. Peter's Basilica in Rome, Canute the Great introduced the first ever Euro!. In other words, it was called something else, but he standardized the coins in England with those of the German-Roman Empire and Constantinople, so that you had a common currency throughout the Christian world! Trade increased tremendously!

The Netherlands and Belgium.
It was the then rich trading town, Dorestad, founded approx. year 600 at a tributary of the Rhine that attracted the Vikings, The city was sacked 6 times in the 800s, until the city's access to the sea was almost completely closed by a storm surge in 860 and the city disappeared.

The German-Roman Empire, now France and Germany.
Here, too, a larger book would be necessary. France-Germany was then a hereditary empire. Not all emperors were effective. In the 7th century, France was plagued by Muslim armies that moved up into France from Muslim Spain, until in 762 they were defeated by the French and the Burgundians at Poitieres approx. 250 km south of Paris.

In the 8th century, the Vikings came!
The Vikings sailed up rivers and streams and plundered the land. In large groups they roamed the country on the country roads the Romans had laid out a century ago. A probably Norwegian viking, Rollo, became a duke in Normandy (from the duchy later came Gorm the Old, among others). The hope was certainly that the Viking duke would calm down his countrymen. The great pagan army ravaged southern France from 850-65. Here the provinces had been a little rebellious against the emperor, so the Vikings came conveniently for him. At any rate, he let them pass through the Seine unmolested.

A very young emperor, Ludvig the Child (Enfant), however, gathered an army and beat the Vikings hard, but perished shortly afterwards. He saw a lovely girl in a garden, put the horse's spurs to his bidding and rode after her. She ran the other way. As he rode through the archway, he forgot to duck. He died the next day. A peripheral member of the imperial family converted to the asatro, but found field life among the Vikings too uncomfortable and returned to his estates. Here he was seized by stubborn Christians and executed. There was then the death penalty for leaving Christianity.

Spain
In the Viking Age, Spain was Muslim except for a Christian kingdom in the northernmost part of the peninsula. The Vikings also attempted raids in the caliphates there. At home, the Muslims were then well organized and quite effective. The Vikings had heavy losses there.

However, the Muslims were impressed by the Viking ships and one of the caliphs had some copies of the Viking ships made, but they did not live up to expectations. What the Vikings had and the Muslims did not have was centuries of experience with the longships, accumulated over many generations.

North Atlantic. Sea of the Vikings
The Vikings ruled the North Atlantic from approx. year 800 and until about 1020, when Canute the Great took over power in England. No state until then had naval forces to match them.

The ships.
The ships were built of wood, preferably oak. Building them required prior knowledge and experience, i.e. shipbuilders.The ships had oars and the days of the year were quite short by modern standards. The sails were made of wool. Being able to produce textiles from wool was not possible in Northern Europe until the Iron Age, so no ship has sailed here in our part of the world before we could process wool!. The sail was as shortable as the ship and to avoid it being stolen, it was often locked in the holiest place in the area, the church, if there was one.

In the spring, with the church's blessing, you could go out on raids! One would think it was a lie, but the first crusades to Jerusalem from Norway in 1107-1110, led by Sigurd Jorsalsfarer, took place just like that. It was funded by looting on the trip down there! It is therefore not surprising that recent historians see the Crusades as a continuation of the activities of the Viking Age.The ships enabled the Vikings to move almost anywhere there was water. They didn't go that deep. They didn't have a fridge. A witty head once said they could sail on the dew. It is excessive. As a rule, they needed ½ m of water. They could easily run up streams and rivers and anywhere on a beach. You could pull the ships over land or rather push them. Pulled the ships from the front, they broke. You had to have the tow rope at the back of the ships and forward.

The sailing
The lack of keel and small draft made it difficult to cross upwind, i.e. in a tailwind and they were sensitive to crosswinds. Still, they sailed from Denmark, Norway and Sweden across the North Atlantic to the Hebrides, the Shetland Islands, the Faroe Islands and Iceland, even to America. How did they do it?

The ship wing,
A Viking ship was equipped with a ship's wing. It was a piece of thin metal that looked like ¼ of a circular disk and was mounted vertically so that it could turn around a vertical iron rod 20-30 cm. So it was like a modern weather vane.

Under the wing was a horizontal table, which was provided with strips of cloth that fluttered in the wind and also showed the direction of the wind. The wing was mounted close to the helmsman, i.e. at the tiller at the rear on the starboard side of the ship. The position of the wing in relation to the wind and the ship should preferably be the same all the time. Otherwise the ship or the wind had changed direction and the course had to be corrected. The wind direction was expected to be fairly constant, at least for the 12 days or so that the trip lasted.

The wind changed, the skipper had a problem and had to guess how the wind had changed. The Vikings initially had 8 corners of the world, later it became 16, perhaps marked on the table for the wing of the ship. The skipper had some support in the position of the sun and stars, but no sextant and not even a clock. The birefringent sunstone, which could indicate the position of the sun in cloudy weather, is mentioned in the sagas, but has not been found in a Viking context. There are stories of taking birds (ravens) on long journeys and hoping they would fly towards land when released.The ancients did not sail like today's ships, on the clock! They waited and waited, days and weeks, for the right wind from the right direction and only when it came did they sail. The Vikings also knew the currents of the sea, i.e. here mostly the Gulf Stream.

How was that possible.

The climate was different
Experts had previously noticed that the Stone Age settlements in the Ertebølle period were sheltered from the wind from the north-east, i.e. on the south-west side of ridges. Approx. 2000 years later it was the other way around. The prevailing wind direction had thus changed, apparently also several times, also later. When the prevailing wind direction changed last time and the southwest wind became predominant, the wind blew salt water and thus the herring into the Danish waters. The herring fishery there began small in the 1000s and was huge at the end of the 12th century.

In order to skip very technical considerations about weather and climate, we must assume that the climate then was different from now. Even if today's climate fanatics don't want to know it, the climate and weather in Northern Europe and the Atlantic Ocean have had alternating hot and cold periods of 5-600 years duration for the last 5,000 years. We are currently on our way to a new warm period. The wind direction may similarly have periods of about 2000 years with changing prevailing directions. The Vikings lived in a warm period that had begun after the Iron Age and continued into the Cold Period of the Dark Ages, which was noticeable at least in the 14th century.

In the Viking Age, the prevailing wind came from the Northeast and when the wind was in that corner, it was stable for a long time. They therefore used a Viking ship closest to the direction of the wind as a compass needle. Should one go to e.g. Iceland, you first sailed to a certain place in Norway, here Bergen or Trondheim. From here, when the wind was suitable, you sailed with the north-east wind obliquely from behind due west, until you entered the westward part of the Gulf Stream, which first took the ship to the west under Iceland. The course was kept with the ship's wing.

Greenland trip - but not return?
If you were to go to Greenland, but continue on the same course, and would then hit Greenland approx. 180 km north of the southern tip of Greenland. They wanted to avoid sailing south of Greenland and ending up in America. On the east coast of Greenland, you entered a cold, south-going East Greenland Current, which turned slightly north at Cape Farvel. You turned with the current at Cape Farvel and sailed north in a short, north-going West Greenland current to Østerbygden. Vesterbygden was then a further 6 days of rowing north. No help for sailing north from either wind or current!The settlements were founded in the 9th century by Erik the Red and his son, Leif the Happy.

If you wanted to sail from Greenland to Iceland, you had a problem. The Gulf Stream and the wind went west, thus giving a counter current of at least 2-3 knots. You could only get there by rowing.Instead, you had to set a course south and aim for the islands in the Atlantic or Scotland and from there turn north into a northerly current up past the Norwegian coast and from there again west on the route to Iceland. So those who lived in Greenland had a problem! The northerners quickly found America and settled here too, but came to war with the Indians and left America again.

There were lots of trees and timber in America, which the Vikings called Vinland (It can also mean borderland), but they had the same problem with getting from America to Greenland. The current and the wind were against them. They tried to get timber from the forests in Vinland anyway, but since they had to row with oars on the way home, more men were needed and then they couldn't get enough wood either. From Alaska and the rest of North America, a lot of driftwood came to the shores of Greenland. If necessary, it could be used to repair the ships, but not to build new ones.

When the Norse colonies in Greenland sang the last verse, their ships were up to 350 years old, i.e. far beyond the ships' natural age and were hardly seaworthy in the Atlantic. Presumably Europe's interest in the ivory from walruses and narwhals from Greenland also cooled in the 14th century, when after a century's break ivory could again be obtained from Africa. It was no longer worthwhile to sail to Greenland after that. In addition, a cold period was on its way. The sea ice in Greenland became a nuisance. Traffic between the settlements ceased.It is known that a wedding was held in Østerbygden in 1408. That is the last you hear of the Norsemen in Greenland.

One is inclined to think that many of the last inhabitants, especially in Vesterbygden, died at sea in an attempt to connect with the others to the south. After this sad depiction, a story about what the Viking ships could really accomplish is in order.

Viking ships sail across Thy!
In the summer of 1061, the Norwegian king, Harald Hårderåde, sailed with light ships into the Limfjord through the eastern opening, which was so narrow that only one ship could pass at a time. The Norwegians came to plunder the Jutland on both sides of the fjord. While they were doing this, the Danish king, Svend Estridsen, had his ships assembled to pursue Harald and perhaps capture him. There were also Danish Vikings at the western exit of the Limfjord. It took a long time for Svend to get through the entrance with all his ships.

Meanwhile, the Norwegians had run out of water. A barrel of water used to be at the back of a ship on the port side. The water in the Limfjord was obviously brackish or salty. Harald then sent the people out to catch a viper. When this was done, the worm was roasted a little over the fire, and having a string from a key attached to its tail, was set free. With the string, the Norwegians could now find where it had crawled into a hole in the ground. They dug there and found water. The story sounds like it was made up for the occasion. Perhaps it was meant to show that the Limfjord was salty and therefore open for passage at the western end.

At night, the Norwegians pulled the ships over a isthmus and the next day they could sail up Kløv Å and a number of other streams, lakes and swamps into Vigsø Bay.

"By the hands of the Danes
Harald slipped away
what they hollered."

How could it have been done? Today, no one would be able to do that to him!Yes. The tectonic plate on which Denmark lies has, since the end of the ice age, tipped over a line, approx. through Nyborg and Fredericia. South of the line the land sinks, north of it the land rises. Thy has therefore risen and was then between 4 and 7 meters lower than it is now. In the South Funen Archipelago, the country sinks approx. 1m every 1000 years. Thy was a swamp area in the Viking Age. There was even a Ferry Castle with an associated ferry in Thy. Harald must have studied the terrain in Thy thoroughly before the trip.

The Danes conquered England and 100 years later the church would not know about it! Twice Danish kings have come sailing with Viking ships and conquered England. Saxo writes in his History of Denmark, a good 100 years after the last great conquest, nothing, nothing at all about this! On the other hand, Saxo tells about Svend Tveskæg, who conquered England in 1012, that Svend was captured three times by the Jomsvikings and ransomed with his weight in gold and double his weight in silver. Today's Viking Age historians say briefly about the captures: "It's all a lie!" Well yes. They use slightly nicer words!

Saxo probably knew that well too. He had written after Thietmar of Merseburg (died 1018), who wrote, Svend was captured once and Adam of Bremen (died c.1081), who wrote, Svend had been captured twice. Now Saxo (died 1208) trumped three times. It was all a lie! Svend was in bad standing with the church's historians, They could not even agree on whether it was Harald Blåtand or Svend Tveskæg who saw Poppo carry an iron burden. That story was probably a lie too! See why Svend was in bad standing in the Danish church!

Yes, Svend tried to introduce the Christianity of the Church of England in Denmark and it was completely wrong. Partly the Christianity of the English was not quite right, partly the church's income had to end up in the right place, namely with the archbishop of Bremen and not the wrong place, namely with the archbishop of Canterbury. This last one in particular was important. The German church people in Denmark actually captured and mistreated the English, indeed they even tried to murder them, says Adam of Bremen. Therefore, Svend was in bad standing with the German church people, to whom Saxo therefore belonged. The true history of England was a no go for Saxo.

Saxo must have known about the English expeditions after 20 years of gathering information on the Danes' exploits! But he wrote alone to transfer all the greatness of Danish history to a completely different person, namely his employer, Bishop Absalon, who at the time probably aspired to become king of Denmark.

Postscript.
Back home in Scandinavia, the Viking ships up until the 13th century were both merchant and warships, until the German Hansa's new type of ship, the keg, appeared. The cog could cross against the wind, load much more than a Viking ship, and keep the goods dry under one deck!. It also required far less manpower. In less than 100 years, they outperformed the Viking ships.

A new era of Danish history began!

The information on navigation in the Viking Age is from the book Svend Larsen: "The sea of the Vikings" FORUM COPENHAGEN 1975..

Svend Larsen was a senior veterinarian in Skive and former chairman of the Danish Sailing Union.

The  ring fortresses  from the Viking age. 

Article written by Ole Jørgen Nørgaard.

The Vikings' ring castles, Aggersborg, Fyrkat, Nonnebakken and Trelleborg were all built almost simultaneously, namely in the years 980-981. The newly discovered castle at Køge is perhaps completely different and is not mentioned here. That the ring castles were built during the reign of Harald Blåtand, no one can dispute either, whether he died in the year 980, 981 or 985 or 986.

They wanted to see the castles as part of Harald Blåtand's collection of the entire kingdom and thus a center for control and administration of the regions and, in case of emergency, military defense installations. This view has a problem! If Harald Blåtand had the castles built, who built them for him?

Ravninge Meadows and Mistakes
The year before, 979, Harald Blåtand had called the court together to build a large bridge over Vejle Å at Ravninge Enge. The bridge seemed to serve no purpose and the court grumbled at being used for slave labor. The bridge was then only an excuse to call the shepherd together. Hirden was the kingdom's armed force, distributed among 200 longships. Harald Bluetooth's own steel fists, the Jomsvikings, also took part, although it is unknown if they also worked on the bridge. When the bridge was almost finished, Harald called the court together in a hollow on the road to the bridge. This valley was very appropriately called the Devil's Valley.

Here he demanded, probably supported by the Jomsvikings with weapons, that the court, who was in work clothes, should support the banishment of the king's own son, Svend Tveskæg, who was very popular in the shepherd and seemed to be a sure successor to the throne. Svend was good at handling difficult situations. He was a lucky man! Harald, on the other hand, had in his time made a number of catastrophic political miscalculations. His claim here was another misjudgment! Suddenly it was his life that mattered!

Svend was popular. It wasn't Harald anymore! The court supported Svend. Harald Blåtand had to save himself by fleeing, covered by the Jomsvikings. He fled with them to Jomsborg, which lay on the Baltic Sea coast in present-day Poland. Did Harald sit in Jomsborg and organize the construction of the castles and administer the kingdom? Barely!

Svend's problem
But Svend now had a problem. His supporters, the fighting force of the kingdom, the 200 longships with armed men, were not full-time warriors. They had farms and properties to look after at home. Sooner or later, Svend had to send the longships home to each of his lordships. When that had happened, the Jomsvikings could come and pick off the ships in one lordship after another and perhaps also the men. That's why the ring castles shot up!

The ring fortresses  are built
Presumably, the idea of ring castles arose as a solution to Svend's problem here. Svend's people, the gradually tried herd, leveled the terrain in the selected places, made roads, paved the future streets, dragged the ships ashore and into the streets, built houses and finally the ring wall with the palisades and the moat. A garrison was left behind, agreements were made on how to delay an enemy coming up the stream towards the castle and the local fighting forces were gathered in the castle in the event of an emergency.

The case was not long in coming. The capital with Svend is attacked. The attack came to Trelleborg on Zealand. The attack came and it came from the hillside, slowly but surely. The king and the king's elite troops: the Jomsvikings. Invincible so far. They had a fire lit in the ring rampart, which consisted of peat soil. It burned! The palisades were burning. Presumably a street with ships also burned. Harald had probably been imprudently hot-tempered or overzealous because he reckoned no one would dare kill the king. Killing a king usually cost life. That was another misjudgment!

Longbowmen versus snipers. Patricide
Many longbowmen, here especially those of the Jomsvikings, work like a machine gun. The arrows fell close within the rampart. Svend was in trouble! Svend also had snipers. He told them to shoot Harald Blåtand. They did! One of the snipers hit him.It was parricide, but the codex at the time said that when one of the leaders fell, the fight stopped. The Jomsvikings stopped the fight and sailed to Jomsborg with the badly wounded Harald, where he died. The battle for the throne was over! The ring castles were no longer needed!

The German Church of Bremen versus the English Svend
The people of the Church of Bremen did not like Svend because he tried to bring Christianity to Denmark from England and thus put the country under the Church of England, so that the flow of money from tithes, episcopal gifts etc. flowed to Canterbury and not to Bremen.

They blackmailed Svend at every opportunity.
They spread rumors that Svend was captured by the Jomsvikings and had to pay a large ransom once, twice or even three times. It is quite certain that the ransom was never paid. It is highly doubtful whether he was held captive at all. He may have used the large amount of money to build the ring castles. There are also two explanations for how he was captured. The most famous is the one where he is pulled from his ship into a rowing boat and rowed away. The other reads, Svend visited the kidnapper in his house and the kidnapper just kept him.

The kidnapper is identified by Snorri as Sigvalde Jarl, brother of Thorkild Høje. Both of these men accompanied Svend when England was conquered.

Earl Sigvalde disappears in England. No further account of him. Maybe died of disease. Neither his birthday nor the date of his death are known. There have been faint conjectures that he did not exist at all. Furthermore, there are also conjectures that the church chroniclers are trying to build their account of Svend's life on a theme from the Old Testament.The church chroniclers also claimed that Svend wandered abroad for several years, exiled from Denmark. Other sources say he was preoccupied with conquering, first Hedeby, a rich trading town and money machine, which Harald had set in a war of aggression against the very young German emperor, Otto II. Svend married the Swedish king's widow and became guardian for her son, the future Swedish king. Later it took some years to organize the conquest of England.

Svend's death and his funeral with an English girl!
Svend died unexpectedly in England. He got sick and fell off the horse. Dying, he asked his young son, Knud, to have his body sent to Denmark, so that the English king would not have to desecrate the body and thus Svend's legacy. England was in rebellion again and Cnut was in a hurry to get away, so he just had Svend's body embalmed and buried in York, Presumably in the cathedral.

In the midst of the new battles for the land, a woman from one of England's most powerful families came to York, probably with armed men. She had Svend's body moved, wrapped in a shroud and placed in a transportable coffin with "smelling herbs". The woman also had a ship equipped and manned and "- guided it by the North Star"-- - to the ports of the Danes - - - Here she sent word to both of Svend's sons and let them know that their father's body was there. They should come quickly and receive it and lay it to rest in the tomb he had arranged for himself.” The brothers did. In the original text it says ports, not harbor, so perhaps she searched one port after another until she made contact. It is not known which ports she came to. There are guesses at Hedeby, Roskilde and Lund (which has no port!). Another good guess would be Vestervig.

Who was the woman? You don't know that!It was long before the Metoo movement; but the story says more than many words about both the girl and Svend.Did the Church of Bremen hit on Svend in the end? Medieval accounts say that Svend was buried in Roskilde Cathedral. You just don't know where!Considering the Bremen church's attitude towards Svend, one can have doubts about where the body ended up and hope that his sons kept an eye on it.

Shot while going to the toilet?
There is a festive story about how, one evening after a fight against Svend, Harald Blåtand went aside to perform his emergency treatment and just as he was about to sit down with his tail bare, he was hit by a shot right in the middle of the balls, so the arrowhead stuck out of his mouth and the quills out of the end. (Icelandic Saga)
The story is written by someone who has never been on a train himself. When you had to do your emergency on a train, you didn't sneak out into the surroundings alone. It was life-threatening. You went around and asked your comrades if they were also going and then several of you went in a group. A king was always accompanied by at least 4 men, especially in such a situation, precisely because here he was particularly vulnerable.

Svend passed on his death!  In 2015, Svend Tveskæg gained new relevance. It was probably the well-known Danish forensic pathologist, Jørgen Lange Thomsen, who became aware that Svend Tveskæg had obviously passed on a legacy for Sudden Unexpected Death (PUD) to his descendants. The disease was first described in 1992 and is called Brugada Syndrome. The defect is located in an X chromosome and is autosomal dominantly inherited. It is a defect in the nervous system that controls the heart and can therefore dictate a sudden cardiac arrest.

Svend himself died Suddenly and Unexpectedly! A count of 29 male descendants in several lines of said king shows that 6 have died a natural death, 8 were killed and 15 died of PUD, i.e. Sudden Unexpected Death. Something is enough about that!

Svend's mother?
While there was no doubt that Harald Blåtand was Svend's father, it is not known for sure who his mother was. It is fairly certain that she was rejected by Harald and replaced by a perhaps younger and at least politically more correct woman. The sources list three possibilities: Tove, Gunhild or Gyrith. There are strong indications in the sources that she and her son, Svend, were forcibly moved to a wasteland in the most remote and darkened part of the kingdom. One actually assumes that the place was Søllested near Assens on Funen.

In 1861, a farmer in Søllested removed a mound on his field. There is no doubt that the mound was a plundered prince's grave from the Viking Age with the remains of a magnificent chariot. The grave later turned out to be the largest known Viking Age burial in Denmark. The finds in the mound were later dated to o 960. As the dead body was piled in a cart and not a ship, it is assumed that it was a woman. The hill was also called Svends Høj. The archaeologists believe that Svend built the mound over his mother. Most likely she was the Swedish royal daughter, Gyrit.

Svend may have lived on Funen in his earliest childhood, but as a very young teenager his father sent him to a forced upbringing with the Jomsvikings. Before this he hated the father. After this, he intensely hated both the Jomsvikings and his father.

And right at the end:
Blue tooth?  Did Harald have a black tooth? Barely. There are two explanations for the nickname. Gr. English: Tan can mean skin, i.e. Blue tan = dark skin = blue in the head. Tan can also mean (lesser) chief. (Palle Lauring: Danske Konger) Freely translated: The little angry man who thinks he is something! Perhaps Svend's vikings in England called him that out of spite.

Thyra: Speaking of names; On one of the Jelling stones, the name "Thaurui" is written in runes (Th means pronounced soft d). How to get it to Thyra? Yes; Saxo had to use a Latin name for his chronicle, so he translated it to Thyra and it has been used ever since!

Brother Otto?  Svend had been christened Otto as part of a peace treaty after one of Harald's lost wars. One of the peace conditions was that the royal family should be baptized and become Christians. Svend was named after the victorious German emperor himself, Otto, who personally benevolently gave him his name! 

This did not prevent Svend from later conquering Otto's new fortress at Hedeby. Several attempts to reconquer Denmark with a large number of men had failed, then came the strategist Svend. He sent a burning longship into the city's harbor. Everyone rushed to put it out, including the castle's crew. Svend's people took over the castle. So easily it could be done!

Materials:
Poul Skåning: "Svend Tveskæg. The builder of slave castles and the conqueror of England" Poul Skåning and Forlaget Hovedland 2008.
ISBN: 978-87-7070-073-3.

Marie Hellberg and Jørgen Lange Thomsen; "What did the royals die of" 2015 FADL's publishing house Copenhagen. ISBN: 978-87-7749-768-1

Palle Lauring: Kings of Denmark. Audiobook. Saxo.