Original subtitles

On the shores of Sandwich...

...a man walks in silence.

His name is Knut,

a Viking prince born into a line of kings

who have ruled Denmark for more than half a century.

A few days earlier, he believed he could rely on a pact

his father had forged with the English nobility.

An agreement that he thought would make him King of England.

But the lords turned their backs on him.

And today, it is their sons who will pay the price.

Many of these hostages may have been young men

not much older than him.

In many ways, that highlights the ruthlessness

Knut was wishing to demonstrate in this particular action.

He is only 20 years old, but Knut does not tremble.

With a single gesture, he orders the hostages to be mutilated.

Noses.

Ears.

Hands.

Just enough for England to understand.

He's not killing them.

He wants these people to go back and send the message,

“Don't underestimate me.”

In his eyes burns a cold fury.

He swears he will return.

And this time, he will take England.

On the shores of the Roskilde Fjord,

Knut watches the longships approaching.

On board stands his brother, Harald.

As always, a single glance is enough to spark a furious race.

Not for the thrill of the game, but out of defiance.

Between the two brothers, everything already seems written.

It is not Knut but Harald who will wear the crown.

Knut is the second son,

and I think that's important in understanding the man

and understanding his ambitions.

He can be Prince Harry to Prince William.

As long as Harald stays alive,

Knut is not really going to be in a substantial position of power

in Denmark.

So there was a lot to play for.

And that probably explains some of the jockeying

and competitiveness we often see amongst heirs in this period.

Ideally located at the crossroads of the North Sea

and the Baltic Sea, the Kingdom of Denmark

is one of the most powerful and feared realms in Scandinavia.

Its coastline, scattered with islands and carved out by fjords,

shelters natural harbours where hundreds of merchant ships converge.

Like in Roskilde, the capital.

The merchants' stalls overflow with the riches from the East and West...

...amber, furs,

weapons... and slaves.

For Knut, who has never left his homeland,

these treasures are a call to adventure.

The kings of the Danes could be split into two categories -

kings of the land and kings of the sea.

Those who stay in the country and govern it,

and the younger sons, often chose the sea,

setting out for adventure in England, West Francia or elsewhere.

It seems Knut was raised with that very purpose in mind -

to conquer, to wage war, to amass wealth abroad,

and then return home to carve out his own share of power,

by force or by strategy.

Knut’s thirst for power comes from an extraordinary lineage.

A grandfather, Harald Bluetooth, who, for the first time,

united the kingdom under a single crown.

And a father, Sweyn Forkbeard,

a feared Viking warlord who has ruled Denmark for over 20 years.

A lineage forged in blood and betrayal.

Harald Bluetooth was a long-ruling

and highly successful king,

and therefore his son Sweyn was chomping at the bit

because it was, of course, in the interest of Sweyn

to gain as much power and authority as possible as quickly as possible.

And it's in Harald's interest to prevent him doing so,

because only one can be king at the same time.

And it ends up in battle.

Again, we don't know where the battle was,

but we do know that Harald is injured

and he retreats to his allies in the Baltic where he dies.

Sweyn has seized power through the murder of his father.

This is not a strong beginning.

This is a weak and wobbly start.

It is in a world where loyalty hangs by a thread,

and power is won by the sword that Knut comes of age.

A ruthless world that, one morning, comes knocking at his door.

King Sweyn summoned him to his hall.

Knut does not yet know it, but his father has made his decision.

Within weeks, they will march on England.

The 11th century was a major target for the Vikings.

It's wealthy, it's organised, it's bureaucratic.

The English have produced a money-making machine.

Trade is going well.

There are large amounts of gold and silver lying around, and it's close.

This time, it is no mere raid.

Sweyn is aiming for the entire kingdom...

and above all the crown of England.

And so, one way of solving the problem

of only having one Danish kingdom you can give to your sons and heirs

is to conquer another kingdom and to offer prospects to Knut.

So at the back of his mind, probably, is that he'd like to have

and control England himself, but if he takes England,

England can then be Knut's.

Knut is stunned.

To conquer England?

Never before had a Viking dared to imagine it.

For the first time in his life, Knut glimpses a spark of hope,

the chance to break free from his place as the younger son

and finally forge his own destiny.

In his palace, King Aethelred hastily gathers his counsellors.

They confirm what many feared -

a massive fleet is assembling in Denmark.

There is no longer any doubt.

The Vikings are coming back.

It's very likely that Aethelred would have known

about Sweyn's invasion project.

I think with the amount of traffic across the North Sea

during the late Viking Age,

rumours that something was afoot would be very likely

to reach the English court at this time.

The nobles know it. They cannot now rely on Aethelred.

Rarely in the kingdom’s history has a king faced such open doubt.

For over 20 years, men from the Northmen have ravaged his lands.

And for over 20 years, Aethelred has failed to stop them.

And of course, paying tribute

has almost become the default solution.

Whenever a fleet appeared,

Aethelred seemed to offer greater and greater sums.

He is often portrayed as the archetypal weak king,

a ruler who preferred to pay off his enemies rather than fight them.

Ever-heavier tributes have drained the kingdom.

His subjects are weary of a king unable to put an end

to this infernal spiral.

But this time, Aethelred believes the outcome may be different.

He has secured a powerful new ally...

...the Dane, Thorkell the Tall,

one of the most feared Viking leaders of his age,

and, above all...

...a sworn enemy of Sweyn Forkbeard.

Thorkell the Tall is the greatest worry for the Danish kingship.

He's a member of the elite of eastern Denmark,

so the southern tip of Sweden.

This is an area that Knut's dynasty has pushed aggressively into.

And he has seen his power and his wealth

and his privilege being eroded, and he's not happy.

Four years earlier, in 1009,

Thorkell had fled Denmark with 45 ships.

For three years, he ravaged England,

leaving death and chaos in his wake.

To stop him, Aethelred once again chose to pay.

But this time there was a condition.

At this point in 1013,

Thorkell had signed up with Aethelred the Unready.

He was taking Aethelred's money, providing protection.

He pays them to be his private bodyguard.

If you've got one of the largest and scariest Viking armies

and you pay it to work for you,

sitting in England, frightening off other Vikings,

well, this is a brilliant idea!

So the strategy here really is to set a thief to catch a thief,

to use a Viking to stop future Vikings.

And that's his hope, really, is that Thorkell and his formidable army

will be able to stop people like Sweyn.

Aethelred and Thorkell struck a pact.

In exchange for a generous tribute,

the Dane would place his men and his 45 ships

at the King’s disposal.

Sweyn and Knut would now face not only Aethelred’s army,

but a seasoned Viking force hardened by years of raiding.

Sweyn learns of the alliance between Aethelred and Thorkell

and immediately understands that time is running out.

He knew that his old rival’s loyalty belonged to no-one but himself.

Behind this alliance of convenience,

Thorkell is pursuing only one cause - his own.

Thorkell clearly poses a threat to Sweyn and Knut,

because he's shown just how weak the English regime now is,

and he's come within a whisker of conquering England himself.

So it may well be that he himself is harbouring ambitions

that at some point he might just move from being the leading general

to being the ruler of England.

And so for Sweyn, it's a matter of trying to take England

before Thorkell does the same.

At the start of spring, Sweyn issues a great call to arms

across Scandinavia.

Each noble is ordered to provide men, weapons, provisions,

and to join the gathering fleet.

This is the first time that a king of Scandinavia

has called for such a campaign,

and he's drawing in people from all across Scandinavia.

It's an invasion, it's not raiding. And that's the key difference.

On foot and on horseback,

thousands of Danes, Norwegians and Swedes converge on Roskilde.

Soon they are joined by hundreds of fortune-seekers.

Within a few weeks, several thousand men

and more than a hundred ships gather under the King's banner.

So we are looking at a scale of attack

which is certainly very different to those England had traditionally seen

in the earlier Viking ages.

So this is a very, very large army

that can rival any of the English armies.

Knut watches the constant movement on the docks

and the forest of masts stretching across the horizon.

He could feel it.

Everything in his life had led to this moment.

From a very young age,

Knut would have been trained up to be a warrior.

So, crucial to his upbringing would have been

learning those skills of war, honing them through things like hunting,

but also alongside that, learning the tricks of the trade at court,

where also politics was an important consideration,

where making deals where hard-nosed realpolitik

was also something to be learned at a very young age.

Setting aside their rivalry,

Harald greets his brother one last time.

Their father had entrusted him with the regency of Denmark,

confirming his status as the rightful heir.

Knut has no choice. If he ever wished to rule,

he would have to carve out his own kingdom.

At dawn, the armada weighs anchor and turns west.

Onboard, father and son share the same dream -

to conquer one of the richest kingdoms in the West.

The task is immense,

and Sweyn expects Knut to stand by his side.

The role that Sweyn wants for Knut

is as a junior partner.

It's very handy to have a member of your family

who's able to provide some leadership within the Danish army.

But Sweyn also knows that his son still has much to prove.

His first lesson will be to earn the loyalty of his men.

At the heart of any Viking expedition

lies the ability to reward followers.

And obviously, if a leader is able to distribute wealth, gold

and precious metals, it tends to secure his men's loyalty.

The second essential factor is prestige,

delivering victory and leading successful military operations.

Within days, the fleet will reach the English coast.

There, the young prince is about to shed his former self

and embrace his destiny

as a warrior, a Viking, a war leader.

Once again, Aethelred prepares to face the fury of the Northmen.

All his hopes now rest on Thorkell.

He orders him to deploy his fleet at Greenwich, along the Thames,

hoping to lure Knut and Sweyn into a trap.

But one question torments him. Could he truly be trusted?

Aethelred knew his own fleet would be powerless to stop the Danes.

Yet just five years earlier, that same fleet had seemed invincible.

Aethelred had, amongst his attempts

to face down the Viking threat,

sought to reinforce England's naval capabilities.

And he raises a very, very large navy

with the prospect of preventing future invasion.

Shipyards across the kingdom had been mobilised.

Within months, an armada of 300 brand-new ships

gathers along the southern coast of England.

Never before had an English king achieved such a feat.

Everything seems to be going well,

since 300 ships are more than the Danes seem capable of assembling

at that time. But there's a major problem -

the leadership within the Anglo-Saxon forces.

Aethelred entrusts command of the fleet

to two close nobles of his inner circle -

Wulfnoth and Beorhtric.

But one evening, a quarrel broke out.

The two men accuse each other of treason.

In a fit of rage, Wulfnoth seizes twenty ships...

...and rebels.

And so he takes a portion of the English fleet off with him.

The rest goes to try to chase them,

and then a storm dashes them entirely.

Many of the ships sink.

The survivors who manage to reach the beach are slaughtered,

and the ships are set on fire to Wulfnoth's initiative.

A single dispute was enough to set the fleet ablaze...

...along with the last hopes of the English people.

The irony is that in 1009, shortly afterwards,

Thorkell the Tall arrived at Sandwich with barely 50 ships,

a relatively small force, and he meets no resistance at all.

And so what was, in essence, a very good strategic plan

is completely undermined due to divisions within the English camp

rather than any battle being offered with the Vikings.

After ten days at sea,

the fleet finally reaches the English coast.

The island has more than 12,000 kilometres of coastline,

countless possible landing points for the Vikings.

The geography of the English coastline

contributed enormously to the success of Viking raids,

because Vikings could move very rapidly around the coastline.

And so consequently it's virtually impossible to defend.

So it is unfortunately perfect for Scandinavian attack.

An unfamiliar landscape, and yet strangely familiar.

He remembers the evenings of his childhood,

lulled by tales of raids and battles.

And one name keeps coming back...

Sandwich, an English town,

invaded many times.

Among the entry points into England,

the port of Sandwich is extremely important,

as it allows ships to be sheltered quite easily.

It also offers easy access to the mouth of the Thames.

It is difficult to secure for defenders

and easy to access for attackers.

An ideal place to launch an invasion.

Knut leaps from the ship

and for the first time sets foot on the soil of the Kingdom of England.

What does he feel? Excitement?

Rage?

He probably has no time to wonder.

On the beach, English soldiers are trying to stand in their way.

For the young Dane, it is a baptism of fire

and perhaps his first chance to prove himself.

All of these great Scandinavian leaders are warriors;

and lead troops into battle, and clearly are battle-hardened

and known for this fact. That is a big part of their reputation.

At the same time,

they are almost certainly not normally

in the front line of the fray.

So as a Scandinavian leader, you need the respect of your men,

you need to be known as a formidable warrior,

but you also need to not be silly and ridiculous

and take unnecessary risks.

And Knut is an excellent example.

We rarely see him fighting, except when he knows he will win,

which is quite wise of him.

The English troops are quickly defeated.

The Vikings set up camp for the night.

Around the fire, Sweyn and Knut ponder their next move.

England is divided into several Anglo-Saxon kingdoms...

Mercia to the west...

Northumbria to the north...

East Anglia to the east...

And Wessex, the centre of power, to the south.

That is where Thorkell deployed his fleet to defend London.

Sweyn knows that attacking head-on would be suicidal.

Thorkell is very frightening for Sweyn,

presumably because he is slightly scared that he might either not win

or damage an enormous part of the Danish royal forces.

If we add to this the fortifications

of the city of London,

then yes, it clearly becomes very difficult for Sweyn.

He could go straight for it, but that would involve a real risk.

Avoiding Thorkell is therefore the logical choice.

At first light, Sweyn and Knut weigh anchor.

They sail north, and at the mouth of the Thames they turn away,

leaving London behind.

They head toward the Danelaw,

a vast territory stretching from East Anglia to Northumbria,

where Viking influence runs deep.

Danelaw is a term which is used to refer to

the areas in England

which were settled by Scandinavian settlers from the early Viking Age.

It does mean to say that there was a significant Scandinavian,

particularly Danish, influence.

These people are both simultaneously

Scandinavian and English.

They don't see themselves, I think, as allied to either party.

Sometimes they work with the Danes, sometimes with the English,

but they see themselves as a unit in themselves.

I think that's what attracts Sweyn Forkbeard.

He recognises the Danelaw as somewhere that looks like home,

and he knows how to rule that area.

He knows how to control this.

Sweyn and Knut are taking a gamble.

If there is one place in England ready to welcome them, it's there.

Here, resentment toward King Aethelred runs strong,

a resentment born of a past neither Sweyn nor Knut has forgotten.

As England buckles under Danish attacks

and the ever-growing weight of tribute,

the nobility grows restless.

Determined to regain control,

Aethelred makes a drastic decision.

In November of the year 1002,

he sends messengers across the kingdom.

On St Brice’s Day, the 13th of November,

armed men slip silently through the sleeping streets of towns

and villages across the Danelaw.

The Brice's Day massacre becomes one of those very storied events

of Aethelred's reign, and it's the first real sign

that panic is starting to grip Aethelred’s court.

The logical, perhaps more sensible, measured responses have failed.

And so he starts looking to more extreme measures.

And what he fastens upon is the idea that the Danes

who are resident in his kingdom, the Scandinavians resident his kingdom,

are plotting against him. And so he decides to kill them all.

In York, the Danes are hunted down

and enter into a church where they seek refuge.

But outside, torches arc through the air toward the sacred building.

The St Brice's Day Massacre is quite a stain on the reputation

of King Aethelred,

because whatever the scale of the St Bryce's Day massacre,

it had an impact across the world

connected with the Danes.

It must have been in the back of the minds of some of the Vikings

who were present in England in Sweyn's army.

Aethelred believed he was securing his kingdom.

Instead, he unleashed a terrible storm.

Now, who can say whether the people of the Danelaw

will remain loyal to him?

Sweyn and Knut’s ships sail up the estuary of the River Humber.

They then enter the calm waters of the River Trent.

On deck, Knut remains watchful.

He scans the riverbanks, alert to the slightest movement.

He has not forgotten the tales of the elders.

Venturing deep into the English countryside is never without danger.

Since the 9th century,

the Anglo-Saxons have established a network of fortifications

known as the burhs, which were a kind of fortified strongholds.

Some were old restored Roman fortresses;

others were exceptional natural sites, headlands or cliffs

that were walled off to create a fortified point

that was difficult to seize.

Their purpose was to protect merchants, shelter populations,

and, above all, to create a defensive mesh across the territory.

When you look at the map of these burhs, it gives the impression

of a tight mesh, designed to prevent any Viking army

from slipping through the net.

The fleet reaches Gainsborough,

a small, fortified town south of York.

Sweyn orders the landing.

For Knut, who is experiencing his first military campaign,

everything seems too easy.

Since leaving the North Sea, nothing has stood in their way.

No traps, no ambushes.

This is an area of England which is often been distant

from royal control and power,

naturally suspicious of English monarchs at the best of time.

That means that when Knut and Sweyn land at Gainsborough,

they’re rapidly able to gain the support of the local population,

and they almost certainly know that in advance.

It's no accident that, instead of attacking the South of England,

the heartlands of the English kingdom,

they go to precisely where there is the chink in Aethelred's armour.

A group of horsemen approaches the camp.

At their head rides the powerful Uhtred of Northumbria.

He comes to request an audience with Sweyn.

Knut watches him in silence.

Here stands the enemy he expected to fight.

But Uhtred has not come for battle.

Instead, he offers his submission,

that of Lindsey and the Five Boroughs.

To Knut, raised in the Viking code of honour,

this surrender without battle or glory

speaks volumes about his adversary.

What we have to realise at this time

is that the idea of English unity

is only a relatively recent construction

of the tenth century.

And for Uhtred it was probably his interests

to submit to a Danish lord

rather than a distant English king in the south of the island.

It seems he was caught off guard,

that he is defending his own interests in an unstable situation.

Separated from the main Anglo-Saxon army, he knows no help is coming.

For him, it becomes a matter of realpolitik.

If he does not submit, he knows he will die.

Thus he becomes Sweyn’s ally, at least in the short term.

As a pledge of good faith, Uhtred does not come alone.

He brings with him the sons of the Great Northern families

sent to serve as hostages...

...young men barely older than Knut himself.

And yet everything separates them.

On one side, the young conqueror.

On the other, an unarmed youth,

handed over as collateral for an oath.

If you come to an agreement with anybody in politics

in this period, you take a hostage,

to make sure the man is going to do what he's going to do.

And those hostages are then a token of their seriousness.

They have to be very high-ranking individuals,

and they are your collateral.

And this is saying, "We're not going to leave them

tied up to a radiator with handcuffs on.

We will treat them with honour, with dignity.

But if anything should happen, then it's the end of your son here."

You know, this is a very practical guarantee,

but it's also playing on this idea of honour as well.

Without spilling a drop of blood,

Sweyn and Knut seize control of Northern England.

But for Sweyn, this is only the beginning.

What he wants is the crown.

The Northern nobility gathers and proclaims Sweyn King of England,

rejecting Aethelred.

But the rest of the realm still has to be persuaded to accept

such a dramatic change of allegiance.

And what better way to seal that bond than marriage?

A union between Knut and a young noble woman

from a powerful Anglo-Danish lineage

could ease tension and seal alliance.

Her name is Elgifu, from Northampton.

Elgifu of Northampton is the woman that Sweyn Forkbeard

looks at the political landscape of the North and says,

"That one! She's the one that's going to marry my son

because she's the one who can help us control this region.

She's the heiress to this old political machinery."

She is the daughter of Althelm, who had been an ealdorman,

so the leading man in the southern part of Northumbria.

But he had been murdered in Aethelred's court in 1006

in a purge.

But that family nonetheless remains important

and very alienated from Aethelred.

And so, in a sense, she can be a lightning rod

for channelling that dissent towards support for Sweyn and Knut.

And so for Knut, coming in with Sweyn,

perhaps also at the back of his mind,

the prospect maybe of becoming an eventual king of England

or an under king of England under his father.

She is the perfect match to make in that moment.

Knut knows exactly what Sweyn expects of him.

Without hesitation, he leads this perfect stranger to the altar.

And under his father's watchful eye, he takes Elgifu as his wife.

The young prince understands that his destiny is now lying here.

The path is set. Knut will not look back.

At the end of summer, Sweyn orders his army to prepare...

...supplies, reinforcements, horses.

To his seasoned warriors are added the levies raised in the Danelaw.

Before departing, he entrusts his son with the reins

of the conquered territory.

Knut might have preferred to march to war.

But instead, another trial awaits him.

In his father's absence, he must guard the fleet,

watch over the hostages...

and raise the funds needed to sustain the war.

Sons are expected to be trained up in kingship

and to learn the tricks of the trade as soon as possible.

And one of the best ways to do this for someone like Sweyn,

to ensure his sons that experience,

is to allow them an element of rule while he's still alive.

So we're seeing him potentially setting up Knut as his under king,

his representative in England.

And the sense of responsibility that this new conquest,

this new land, this new world, as it were,

that they've struck into, is now his to control.

It must be overwhelming. But simultaneously, simultaneously,

steps up to the plate.

Is it a mark of trust being placed in him?

Partly, perhaps.

But what always strikes me is that Knut still does not fight.

He's not on the front lines learning how to lead an army.

He really gives the impression of being kept safe in reserve

by his father.

In a way, he is already being shaped into an administrator

who's learning governance, which is, in fact, rather wise.

For the young Viking, the moment of truth has come.

Knut watches his father disappear in the distance.

Now alone, he must prove himself worthy of the task.

More than anything, he must ensure his father will be proud of him.

Sweyn’s long column of troops stretches southward,

towards the heart of the kingdom.

But instead of heading for London where Aethelred awaits,

Sweyn leads his men west, towards Oxford.

Sweyn's decision to attack Oxford rather than London

almost certainly is suggestive of serious strategic calculation.

While Aethelred's regime has shown itself to be toothless in many ways,

not very successful on the battlefield,

it remains capable of deploying armies of a large scale

and it still has the forces of Thorkell the Tall at Greenwich.

If Sweyn had rushed his campaign and gone for that,

then potentially this might have been game over for Sweyn too early.

And it made sense to essentially take the pieces on the playing board

first of all, before going to London.

In early autumn, the invading army

crosses Watling Street.

This ancient Roman road runs across England from east to west

and marks a symbolic frontier between the Danelaw

and the Southern lands still loyal to Aethelred.

Sweyn’s orders are clear. Beyond this line, there will be no mercy.

From farm to farm, village to village...

...his army unleashes its full destructive force.

There's no Geneva Convention,

so the objective is to put pressure on the enemy, to scare them.

Men loot, kill and burn as they please.

It’s a phrase frequently used to describe Viking armies.

Psychological warfare is nothing new - it exists in every conflict,

in every era. And for civilian populations,

it has always meant the same thing throughout history.

Raiding the countryside, seizing resources, living off the land,

and killing a few people in a particularly dramatic way

are all part of the usual practices.

After a few days, Sweyn and his men reach Oxford.

The troops take position before the fortified town.

The city gates slowly open.

A man steps forward and speaks a few words.

“The city surrenders without a fight."

The inhabitants of Oxford had already suffered greatly

over the previous decade.

Resisting now would mean a second full-scale plundering

or another round of mass destruction.

Clearly, not everyone is eager to turn their city

into another Stalingrad.

Surrendering is the logical choice if it spares lives

and avoids crushing tribute.

Sweyn and his men enter the city

after a victory won without a single sword stroke.

The strategy of fear worked.

The local nobility submits.

But for Sweyn, it is not enough.

Sweyn Forkbeard is trying to terrorise the South of England.

He has to subdue that part.

And he's got to do this with big public displays.

The lords of each region must kneel before him in public.

He needs Wessex to be seen to be beaten

and to be to be under the heel of the Danish oppressor.

In the days that followed,

the Southern cities fell one after another.

Exeter.

Winchester.

All surrendered without resistance.

In London, Aethelred remains barricaded in his palace...

more cut off from his people than ever.

He watches helplessly as his kingdom collapses.

Aethelred's passivity has really damned

the reputation of Aethelred.

The 12th-C William of Malmesbury referred to him as being lazy,

essentially, not getting out of bed.

But I think we also have to remember

that he had to rely on

regional governors to raise forces

and his commanders, his aldermen, are unwilling to act on his behalf

while he's in London.

So it's something of a difficult situation

for Aethelred at this time.

As autumn begins, the noose tightens around Aethelred.

From the ramparts, he observes Sweyn's troops across the river.

He knows his survival may depend on what happens here and now.

Losing the city, the last stronghold of resistance against the Danes

would mean losing the crown.

Beyond the walls, Sweyn knows the confrontation will be harsh.

For more than a century, London has remained unconquered.

London benefits from its Roman walls that survived

throughout the Middle Ages and were extensively restored for defence.

It is the nerve centre of Aethelred's defence.

This is where he resides, likely with his household troops.

Thorkell is there as well, probably with his fleet.

And then there's London - large, wealthy, powerful.

The inhabitants do not seem inclined to surrender to the first newcomer.

Sweyn knows a frontal assault would be doomed to fail.

So, to bypass the English defences,

he orders his men to ford the Thames.

It's possible that they tried to cross the river

to the west of London at low tide,

but you have to know the river in order to do this.

The manoeuvre turns into a disaster.

Hundreds of men are swept away by the current

and the river's tumultuous waters.

The likelihood that many men drowned

while trying to do this would have been likely to cause Sweyn

to think about changing the direction of his campaign.

Sweyn is forced to face the truth.

To persist would cost countless warriors

and endanger the entire campaign.

The siege of London ultimately is going to fail.

London is just too tough a nut to crack in Sweyn's time.

So Sweyn pulls out and he heads to the West.

If he cannot force London to yield,

Sweyn may try to isolate it from the rest of the kingdom.

To do that, he must seize

the last key stronghold of Wessex - Bath.

This city, where Aethelred's father was crowned,

enjoys near-imperial prestige

and is home to one of the kingdom's most influential noble families.

This, if you're going to crack an easier nut

and you're going to make an enormous political splash,

do it with these people. They're related to the kingship,

they’re long related to the kingship,

and that is a huge money-making area for Anglo-Saxon England.

If you can break the West, maybe you don't have to break London.

Maybe London will fall on its own.

By the end of 1013,

the nobles of Bath, weary of Aethelred's chaotic rule,

rally to the Dane.

Soon, the rest of the kingdom follows.

Aethelred will have seen it sitting in London

as the lights going out one after another across the entire country,

as they just stopped talking to him.

And when you've got nothing left except the city of London,

then I think you leave.

Abandoned by all,

Aethelred, the last king of a five century-old dynasty,

flees toward Normandy.

And there he can remain, king in exile,

awaiting his moment to reappear.

So he is kind of a bit like the Free French government in London

in World War Two, if you will.

He's potentially there in Normandy as the, to his mind,

genuine English king and the real government,

waiting for an opportunity to step back into those shoes.

Aboard the ship carrying him into exile,

Aethelred watches the English coastline fade into the mist.

His defeat tastes of betrayal.

His people did not raise their weapons to defend him.

The nobles abandoned him for a king from the North.

But Aethelred is not broken.

He swears he will return, whatever the cost.

In Lincoln, Knut awaits his father.

The man he finds is no longer only King of Denmark.

He is now King of England.

Before him stands a transformed son,

seasoned and hardened by the demands of power.

It's a new world.

It's the conquest of somewhere for him to rule.

Harald would now have Denmark, he will have England,

and he is the second son, and he's got the conquest.

But what a conquest.

There is far more money there in England

than there will ever be in Denmark.

And that wealth will be used by his dynasty to push its ambitions

far into Scandinavia,

to rule... we have to use the modern word "empire".

If he ever dreamed of being an emperor,

he did so on the day they conquered Southern England.

Together, Sweyn and Knut have achieved the unthinkable -

seizing the richest kingdom in the Western world.

For the young prince, the future now seems set.

But history is far from finished with him.

England will soon slip from their grasp,

and Knut will be forced to face a new enemy,

far more formidable than any before.

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