Original subtitles

On a late November morning in the year 1095, this man,

Pope Urban II,

delivered a sermon that would transform the history of Europe.

His rousing words transfixed the crowd gathered here in the French town of Clermont.

And in the months that followed,

his message reverberated across the West.

The age of the Crusades had begun.

The Pope proclaimed a new holy war against Islam...

..for control of the most hallowed site in the Christian cosmos -

the sacred city of Jerusalem.

Urban's call to arms initiated a struggle

that would rage for two centuries -

one that fires the imagination

and fuels debate even today.

The story of the Crusades is remembered as a tale of religious fanaticism

and unspeakable violence,

of medieval knights and jihadi warriors,

of castles and kings, heroism, betrayal, and sacrifice.

This feels like you're touching the past. It's an amazing feeling.

But now fresh research, eyewitness testimony,

and contemporary evidence

from both the Christian and Islamic worlds sheds new light

on how it was that these two great religions

waged war in the name of God...

..why hundreds of thousands of Christians and Muslims

answered the call to Crusade and Jihad...

..and who, ultimately, won the war for the Holy Land.

From the summer of 1096,

between 60,000 and 100,000 Christians -

men, women and children - set out to walk some 2,500 miles

across the face of the known world. Their goal? Jerusalem.

Not since the distant glories of ancient Rome had a force of this size been assembled.

Rich, and poor, peasants and knights, these were the First Crusaders...

..Christian soldiers who endured unimaginable suffering and privation

during an armed pilgrimage that lasted for three years.

So who were they? And why did they fight?

When Urban II became Pope, Christianity was in turmoil,

split between the Greek Church of the East and the Latin West.

The papacy itself stood on the brink of overthrow,

embroiled in a long-standing feud with the German Empire.

But Urban had a plan.

Determined to reassert papal authority,

in the autumn of 1095 he came to France, where he would launch

a titanic armed pilgrimage, known to history as the First Crusade.

By November 1095, the Pope was ready to unveil his plan.

Here in Clermont in Central France, he gathered 12 archbishops,

80 bishops and 90 abbots

for the largest clerical assembly of his career.

After nine days of general ecclesiastical debate,

Urban announced his intention to deliver a special sermon,

and on the 27th of November,

hundreds of people crowded into a field outside the town to hear him speak.

"We want you to know what grievous cause leads us to your territory.

"A grave report has come from the lands of Jerusalem

"that a foreign race, a race absolutely alien to God,

"has invaded the land of those Christians

"and has reduced the people with sword, rapine and fire."

Urban's speech was the moment of genesis for the concept of a crusade.

It was primarily designed to meet the needs of the papacy.

And it contained a brilliantly conceived hook.

The coming expedition would target

the greatest pilgrim destination in the Christian world -

the Holy City of Jerusalem,

which lay in the hands of Islam.

But the Pope had a problem.

Jerusalem had fallen to Islam more than 400 years earlier,

so he could hardly claim this as a fresh crime.

To lend urgency to his call,

Urban therefore turned to one of the most powerful and dangerous forces in human history -

the idea of otherness,

of an alien enemy guilty of ghastly crimes who must be repelled.

"These men have destroyed the altars

"polluted by their foul practices.

"They have circumcised the Christians,

"either spreading the blood from the circumcisions on the altars

"or pouring it into the baptismal fonts.

"And they cut open the navels of those

"who they choose to torment with loathsome death,

"drag them around and flog them before killing them

"as they lie prone on the ground with all their entrails out."

The Pope created an anti-Islamic onslaught peppered with propaganda.

His graphic imagery bore little relation to the reality of Muslim rule in the Holy Land.

Nor was Urban's call to arms

directly inspired by any recent atrocity in the East.

Nevertheless, his attack ignited a fire of vengeful passion,

as news of the Crusade resounded across Western Christendom.

The idea of the Crusade was unleashed in a spiritual age -

an era that in many ways is wholly alien to our own.

Today we might be acculturated to notions of tolerance,

scepticism and religious difference, but a singular truth

bound together almost every human being alive in 11th-century Europe,

and that was unconditional and total belief in Christianity.

At the core of medieval Christianity were the twinned opposing emotions

of hope and fear,

the promise of salvation and the threat of damnation.

The Church taught that every human would face a moment of judgment,

a weighing of souls.

Those found to be pure

would be rewarded with everlasting paradise in Heaven.

But if you were a sinner,

then you faced certain punishment -

an eternity of gruesome torment in Hell.

This magnificent sculpture cycle depicts the Last Judgment

and it's the perfect evocation of the whole idea

of agony and ecstasy in medieval Christianity.

It was sculpted, we think, by one of the masters of medieval art -

a man called Gislebertus.

And we know this because he's left in his inscription

"Gislebertus hocfecit" - "Gislebertus made this".

Let's start with the good, let's start with salvation.

What we see amongst the saved

are three children being lifted to Heaven by an angle.

And if we look above

we can see beautiful, elongated angels lifting the saved up to paradise.

On the other side, on Christ's left hand, we see those less fortunate,

those who have sinned and will face an eternity of torment in Hell.

We can see a man bearing a bag, probably a bag of money,

meaning he's a miser or a moneylender.

He's amongst the damned.

And there we can see a woman with a pair of snakes

gnawing on her bare breasts, showing that she was lusty or lewd.

And perhaps most evocatively of all,

a man with a look of fear and agony on his face

as a pair of giant demonic hands reach down to strangle him

and pull him through the gates of Hell.

This is the tableau of horror laid out before you.

This is what Gislebertus wanted his audience to understand -

the consequences of sin in the medieval world.

Primed to seek redemption,

Western Christians were thus enthralled when Urban II

announced his expedition to the Holy Land.

The price would be huge.

The faithful would have to give up everything

to participate in a terrifying, near suicidal journey into the unknown,

but in return, the Pope seemed to be promising

a guarantee of eternal salvation.

Tens of thousands of ordinary Christians

responded to the Pope's brilliantly-conceived campaign.

But Urban's target audience was the aristocracy of Western Europe -

a violent warrior class

fighting for survival in a world of bloodthirsty lawlessness.

These warlords would become the Crusades' leaders -

Christian knights for whom the Pope's call to arms solved a very particular dilemma.

The Pope knew only too well the anxiety of Christian warriors

trapped in a worldly profession imbued with violence,

yet taught by the Church that bloodshed was sinful.

The real genius of Urban's crusading ideal was that it solved this dilemma,

reconciling faith and violence.

Urban spoke of a new sacred struggle,

in which fighting would not simply be permitted,

but actively encouraged and even rewarded.

The day after Pope Urban's sermon at Clermont,

Count Raymond of Toulouse,

the most powerful secular Lord in Southern France,

became the first nobleman to commit to the Crusade.

Determined to prepare his soul for the gruelling expedition ahead,

Raymond then came here, to this cathedral in Le Puy.

The Count made a large donation

to secure the favourable intercession of the Virgin Mary,

and according to one chronicle requested...

"So long as I live a candle should burn for me incessantly,

"day and night upon the altar

"before the revered image of the Mother of God."

Some Christian knights may have embarked upon the holy war believing they would reap rich rewards

from conquest and plunder in the East.

But the vast majority were primarily driven by faith

and the promise of redemption.

It's often argued that Raymond, and many like him,

joined the Crusade in search of material gain.

But I think this theory is simply unsustainable,

given the vast weight of contemporary evidence that shows us the exact opposite.

Raymond actually walked away from one of the richest lordships in Europe to join this expedition.

And like many of his fellow Crusaders,

he probably expected to die in the East.

I think most people joined this Crusade

because they earnestly believed that the coming campaign would cleanse their souls of sin.

They were, I think, looking for redemption in the fire of holy war.

For noblemen like Raymond,

and the retinues of knights and infantry that came with them,

the Crusade offered the promise of eternal salvation,

and, in return, their personal fortunes would bankroll the sacred expedition.

Raymond of Toulouse became the Crusade's elder statesman,

but he was just one of scores of rich and powerful noblemen

for whom the combined allure of military conquest and religious redemption proved irresistible.

There was Godfrey of Bouillon,

a pious duke whose lands extended from North-Eastern France into the low countries of Germany.

Despite a long-standing feud with the papacy,

Godfrey was so enthralled by the crusading message that he joined the expedition to Jerusalem.

There was the Southern-Italian Norman, Bohemond of Taranto,

a guileful military genius, perhaps the greatest general of his age.

And there was Stephen of Blois from Northern France, William the Conqueror's son-in-law.

Stephen left his wife Adela behind to rule in his stead

and later wrote her a series of extraordinary letters from the front line,

describing his adventures in the East.

"In fighting against these enemies of God and of our own, we have,

"by God's grace, endured many sufferings

"and innumerable evils up to the present time."

'Stephen's words survive as a direct, eye-witness account of the Crusade.

'But there were many other contemporaries

'who also sought to chronicle this remarkable expedition.'

This manuscript is a French copy

of the Histoire d'Outremer.

William of Tyre.

It's illuminated.

It is one of our most popular manuscripts

for the story of Crusaders.

This feels like you're touching the past.

It's an amazing feeling.

'This is an illustrated copy, produced in 1289,

'of the most famous chronicle of the Crusades,

'written by William of Tyre,

'a Christian historian working in the Holy Land in the 12th century.'

There's something absolutely extraordinary about being this close

to an item of this kind of rarity.

Such a precious manuscript - to actually be able to touch it,

for me, it's almost electrifying.

This is an absolute masterpiece in terms of depicting

the start of the First Crusade.

And what it shows is a series of knights riding out from Europe,

preparing for their 3,000-mile journey to reach Jerusalem.

And we can see Godfrey of Bouillon himself,

one of the great leaders of the Crusade, in amongst this group.

And he's against a golden background,

and it's that gold that really sets this image alight.

It makes it seem as if the horses themselves are moving,

it gives action, gives life to the image.

And it's that which conveys this sense of a journey beginning - the start of the Crusade.

But this dignified procession belies the ramshackle reality of the First Crusade.

For most people, embarking on a crusade was a colossal leap of faith.

This would be a journey to a wholly alien and unknown world,

attempted with little or no planning and no accurate maps.

This was an extraordinary mass migration

undertaken by over 60,000 people -

an unprecedented tide of humankind.

The first to depart were small groups of peasants and some knights.

Too poor to pay for ships, their only option was to walk,

dragging their few belongings behind on carts,

living hand-to-mouth off the land.

As they marched East, this rabble of Christian fanatics

became embroiled in a series of murderous attacks on the Jews of Europe.

The main contingents of knights soon followed.

But it was only in the first months of 1097,

almost a year after the first pilgrims set out,

that the First Crusade finally united at Constantinople,

capital of the Byzantine Empire.

For most Crusaders, this was the end of the world as they knew it -

a mighty metropolis ten times the size of any city in Western Europe.

And it was the centre of the Greek Church in the East,

the greatest Christian superpower of the medieval age.

Constantinople boasted an unrivalled collection of sacred relics.

It had the Crown of Thorns, locks of hair from the Virgin Mary,

at least two heads of John the Baptist,

and the bones of virtually all the apostles.

And it had this - St Sophia,

undoubtedly medieval Christendom's most spectacular church.

"I arrived at Constantinople with great joy by the grace of God.

"The Emperor verily received me with dignity and honour

"and with the greatest affection as if I were his own son."

The Crusaders had arrived at the gateway to the Orient,

the frontier with Islam.

The Byzantine Emperor had, for some time,

been appealing to the West for help

in defending Christendom's Eastern border.

With the aid of his troops, the Crusaders targeted Nicaea,

an Islamic foothold in Western Asia Minor.

After a month-long siege, the city was conquered.

The holy war had begun.

But there was no immediate response to this audacious invasion.

The Crusaders had, inadvertently, chosen the perfect moment to strike.

The Muslim world was in a state of disarray,

riven by religious and ethnic divisions.

As yet, Islam could not draw upon the same profound sense of shared purpose

that united the Crusaders,

the dream that drove these Christians on towards their sacred objective.

"I tell you, my beloved,"

wrote Stephen of Blois to his wife back in France,

"In five weeks, we will reach Jerusalem."

Because of its vast size,

the Crusade couldn't realistically move forward as a single force.

A column of 60,000 people might take an entire day

just to pass a single point.

And foraging for food and supplies as they went,

they might scour the surrounding landscape like a plague of locust.

Instead, the Crusaders decided to divide their army in two.

Led by Bohemond of Taranto,

the first contingent set off, with a plan to regroup after four days,

here at an abandoned Byzantine military camp,

100 miles south-east of Nicaea.

But the holy army never made its rendezvous.

HORSE WHINNIES IN PANIC

As the Crusaders marched across the plains of Asia Minor,

they were ambushed by a ferocious band of nomadic warriors...

..their first terrifying taste of Turkish horsemen in full flight.

One of Bohemond's followers recalled the moment of horror

as the Turks suddenly came into view

and began to howl and gabble.

HORSE WHINNIES IN PANIC

Another eye-witness, caught in the thick of the fighting, wrote,

"The Turks were howling like wolves."

"They began shooting a cloud of arrows.

"We were all stunned by this.

"Because for all of us, this form of warfare was unknown."

Ranged against a seemingly endless multitude of Turks,

the Christians were thrown into disarray.

Instead of chaotic retreat,

Bohemond managed to establish a defensive formation.

But isolated and exposed, the Crusaders faced disaster.

"Huddled together like sheep in a fold,

"we were trembling and frightened, surrounded on all sides by enemies

"so that we couldn't turn in any direction," one Crusader later recalled.

To strengthen their resolve,

the Crusaders passed a morale-boosting message down the line.

"Stand fast, trusting in Christ and the victory of the cross."

One account described how the Turks burst into the camp,

striking with arrows loosed from their horned bows,

killing men, women and children indiscriminately and sparing no-one on grounds of age.

Stunned and terrified by this hideous killing,

girls who were delicate and nobly born were rushing to get themselves dressed up

and offering themselves to the Turks.

So that at least, appeased by their beauty,

they may offer their prisoners some pity.

This idea of Western women rushing into their tents

to beautify themselves,

all in the hope that they'd be taken slave rather than killed on the spot,

can almost sound comical. But this anecdote is supposed to tell us something.

It's supposed to reveal that the Crusaders were absolutely terrified

by what they encountered at Dorylaeum.

They'd come across an alien enemy - something they'd never experienced before.

What's really extraordinary is that they didn't give up,

they didn't buckle. Instead they managed to re-group,

re-order their lines and hold their position for five hours

until crusading reinforcements arrived.

In the ensuing battle, as many as 4,000 Christians were killed.

But, crucially, the Crusaders simply refused to give in.

The Turks were not defeated at Dorylaeum,

but their resistance was broken,

and the route across Asia Minor opened up.

Empowered by their faith, the Western invaders seemed invincible.

In contrast, Islam's defence lay in the hands

of a disparate array of squabbling warlords.

But the Crusaders faced a different kind of enemy

as they marched across Asia Minor,

enduring the blistering heat of the summer months,

plagued by starvation and thirst.

For the first time, a lack of water became a real issue.

The death rate skyrocketed and there's one thing that's

really extraordinary about this period and that's that the eyewitness testimony

seems to suggest that the Crusaders were almost as concerned, if not more concerned,

about the death of animals as they were about those men and women who died through thirst.

We've always thought that the Crusaders

arrived in the Holy Land with their cavalry intact, the truth is

that, crossing Asia Minor, almost all of these Western horses died.

By the time they reached the Holy Land,

the Crusaders were forced to ride, sometimes on donkeys

with their feet dragging in the dirt, others were astride oxen.

So this idea of an invincible military force,

that the Crusade had at its fingertips, is an illusion.

Christian numbers were severely depleted by an epic journey

that concluded with a terrifying traverse of the Taurus Mountains.

By the time the First Crusade reached northern Syria,

in the autumn of 1097,

only around half of those who had left Europe a year earlier survived.

The crossing of Asia Minor had been an extraordinary feat in itself.

But now, standing at the gateway to the Holy Land,

the Crusaders faced a gargantuan task,

one that eclipsed everything that had gone before.

The conquest of one of the great cities of the Orient - Antioch.

Antioch was a crucial staging post, as the Crusade now looked south

to Jerusalem itself, perhaps less than a month's march away.

But Antioch lay under the rule of Muslim Turks,

shielded by two great mountains,

and a ring of awesome battlements that made this

one of the most strongly-fortified cities in the medieval world.

So this is the iron gate.

I absolutely love this place, because it's the perfect spot to come to if you want to

understand what medieval Antioch would have looked like.

And why the Crusaders thought this city was going to be impregnable.

This is Antioch's last surviving gate, part of a series

of formidable defences that made an immediate attack impossible.

The city was garrisoned by around 5,000 Turks...

..enough to mount a defence

but not sufficient to confront the Crusaders in open battle.

The result, an appalling stalemate that would test

the Christians' faith to the limit.

From the autumn of 1097 onwards, the Crusaders committed

themselves to the grinding reality of a medieval encirclement siege -

a devastating war of attrition that would last for eight months.

That winter would prove to be a living hell for the Crusaders

camped outside Antioch, facing illness, disease and starvation.

The height of the Crusaders' suffering came in January 1098.

Stephen of Blois, who managed to survive these darkest of days,

later wrote in a letter,

"Throughout that winter we suffered from excessive cold,

"and enormous torrents of rain. What some say about the impossibility

"of being able to bear the heat of the sun throughout Syria is untrue

"because the winters there are very similar to our own in the West."

That January, hundreds, perhaps thousands, lost their lives,

not to the edge of a sword, but to illness,

and malnourishment.

Indeed, according to one account,

food became so scarce that the poor were forced to eat dogs and rats,

the skin of beasts and even seeds of grain found in manure.

Many Christians began to question why God had abandoned the Crusade, his sacred venture.

And when it seemed that things couldn't get any worse,

the Muslim world finally appeared to unite.

Just as the advent of spring began to shift the balance

of the siege in the Crusaders' favour,

a dread-laden rumour began to circulate.

Scouts from the Christian camp revealed that they'd seen

a Muslim army.

Reportedly swarming over mountain paths. Like the sands of the sea.

Kerbogha of Mosul, a fearsome Iraqi general,

and some 40,000 Syrian and Mesopotamian troops were

on the way, and now they were less than one week away from Antioch.

This huge relief force, mobilised in response to desperate appeals

for support from Antioch's Muslim leaders,

outnumbered the Crusaders by two to one.

Stranded outside the city,

the Christian army would surely be crushed against Antioch's walls.

Facing the very real threat of panic and mass desertion,

the Crusade's leaders convened an emergency council.

And Bohemond, the military genius who had taken command at Dorylaeum, stepped forward.

Bohemond argued that whoever could orchestrate Antioch's fall

should be given legal rights to the city.

And it was only after the bargain had been sealed,

that the wily Bohemond showed his hand.

Bohemond had made contact with a renegade inside Antioch,

an Armenian Christian tower commander named Firuz,

who was willing to betray the city.

Just a few short days after the Crusaders' emergency council,

a small group of Bohemond's men stole up to the foot

of an isolated section of the city's south-eastern walls.

There, Firuz lowered a ladder.

We know from eyewitness testimony that these men must have been

absolutely terrified, most of them expecting to be killed as soon as

they reached the top.

As it turned out, they were able to despatch the guards

at all the three surrounding towers in almost complete silence,

and soon afterwards a small gate was opened below.

The calm night air was suddenly shattered, a shrill bugle sounded

to signal a wave of secondary attacks on other parts of the city.

And the Christians began screaming out their battle cry,

"God wills it! God wills it!"

The Muslim garrison was thrown into a state of utter confusion

and soon Antioch's remaining gates were thrown open

and the Crusaders poured in.

In the half light of dawn, a chaotic slaughter began

as the Crusaders unleashed eight months of pent-up anger and aggression.

This illumination depicts the fall of Antioch on the 3rd of June 1098.

And I think it's an absolutely remarkable image.

One Muslim is having a sword stabbed through his chest.

Another is about to be decapitated.

And I find this image quite troubling because in many ways it's very beautiful.

The colour is extraordinary, it looks as if it was painted

last week, not 800 years ago.

But, at the same time, it's horrific.

And I think, in a way, this cuts to the heart of the enigma

of the First Crusade and the Crusades that would follow,

because this is about violence that's enacted

in the context of Holy War.

And perhaps in that context the idea that that violence might be sinful,

that it might be morally wrong, has been erased.

Because this was now the work of God.

Having spent eight months battling to gain entry to Antioch,

the Crusaders now found themselves ensnared in a bizarre predicament.

The very next day, Kerbogha's great army began to arrive.

The first Crusaders were now trapped inside Antioch,

the besiegers had become the besieged.

Kerbogha's ferocious army formed a cordon around Antioch.

Trapped inside a city already bereft of supplies,

the Christians now faced the greatest test of their faith.

Food very quickly ran short

and starvation became endemic.

It was said that the poor were forced

to eat the leather of their own shoes,

while others drank the blood from the few remaining horses to sustain themselves.

Many Crusaders now deserted.

Lowering ropes from the walls,

and escaping under cover of darkness, these rope danglers,

as they came to be known, included many well-known knights.

The Crusaders had reached their lowest point.

Weakened by hunger, utterly terrified of the enemy outside

baying for their blood, they were in a state of total despair.

It seemed that the First Crusade was about to end in disaster.

Surely only a miracle could save the Christians now.

In mid-June 1098, a southern French peasant named Peter Bartholomew came forward,

announcing that he'd experienced a series of visions.

In these, St Andrew revealed to him

the resting place of an incredibly powerful spiritual weapon - the Holy Lance -

the very spear that had pierced the side of Christ on the Cross.

Peter Bartholomew led a group of Crusaders

to the basilica of St Peter's in Antioch and began digging.

One member of this party, Raymond of Aguilers, described the scene.

"We'd been digging until evening when some of us

"began to give up hope of unearthing the lance.

"But Peter Bartholomew, seeing the exhaustion of our workers,

"stripped off his outer garments and, clad only in a shirt

"and bare-footed, dropped into the hole"

"He then begged us to pray to God, to return his lance

"and bring strength and victory to his people.

"Finally, the Lord showed us his lance,

"and I kissed its point as it barely protruded from the ground -

"what great joy and exaltation filled the city."

What Peter Bartholomew supposedly found was probably no more

than a small shard of metal.

But the idea that God might manifest his will on Earth

through such sacred objects was part and parcel of medieval Christianity.

And the ravings of a religious fanatic

and the discovery of such a significant relic

had the potential to reignite the Crusaders' belief

in their holy mission.

Most accounts indicate that the discovery of the Holy Lance had an electrifying effect

on the Crusaders' state of mind.

Even though they were exhausted, starving,

and facing seemingly insurmountable odds,

this seemingly irrefutable demonstration of divine support

fired the Crusaders to take up arms and confront Kerbogha head on.

On that day, they scored a miraculous victory,

driving Kerbogha's horde from the field.

Antioch was theirs, and the cult of the Holy Lance was born -

a cult with the power to shape the future of the Crusade.

I've always been captivated by the story of the Holy Lance

and for a long time I believed, like everyone else, that the discovery

of this relic provided an electrifying boost to Crusader morale,

sending them sprinting out of Antioch to confront Kerbogha.

I'd come to Venice to see perhaps the oldest surviving copy

of a chronicle written by Matthew of Edessa,

an Armenian historian who lived during the time of the First Crusade.

It's really exciting to see this manuscript.

Poised between the Western Christian and Muslim perspectives,

Matthew's account offers a more neutral version of events.

So this is the text.

So one of the reasons that I've come here

is because Matthew Of Edessa offer us a unique moment in his text

where he describes what's actually happening in Antioch in June 1098.

Can you show us that specific bit of evidence?

This is the part.

And could you read the section actually in Armenian to me? Yes.

'The Franks became threatened with a famine, because provisions

'in the city had long become exhausted.

'More and more hard-pressed, they resolved to obtain from Kerbogha

'a promise of amnesty on condition that they deliver the city

'into his hands, and return to their own country.'

So Matthew's telling us that the Crusaders

in this month of June, that they actually tried to negotiate

a surrender to be able to leave Antioch - to give up effectively?

Yes, yes. And, er...to have his assurance

that they could turn to their home in, er...Europe.

For so long,

the Crusaders' reaction to the discovery of the Holy Lance

has been held up as proof

of their unshakable, almost blind, piety

but if they did indeed try to negotiate a surrender,

then we're left with a very different image -

one of medieval warriors still wracked by fear and doubt.

For me, Matthew's account is so important - because it allows us

to construct a more human and more nuanced image of these Crusaders.

Kerbogha dismissed the Crusaders' terms of surrender,

leaving the Christians with a hopeless choice -

to die within the city from starvation, or to die fighting.

In the end, the Crusaders did undoubtedly

make an extraordinarily brave decision -

to confront Kerbogha's hoard head on.

But they seem to have done so

not in a state of ecstatic religious fervour

but in utter desperation, expecting to die.

The Christians fought with a primal sense of desperation.

Ironically, facing certain death, with nothing to lose, they won...

..defeating an enemy that turned out to be anything but invincible.

Far from being a united army,

Kerbogha's force was actually a loose and fragile coalition of rival warlords,

each suspicious that Kerbogha himself was hoping to use the Crusader invasion

as a pretext to seize Antioch as his own.

That was why the Muslim army shattered so readily

when struck by the Christians charge,

retreating in headlong defeat.

For most Crusaders, the seemingly miraculous victory over Kerbogha

was proof of the power of the Holy Lance,

and the relic's most ardent advocate, Raymond of Toulouse,

now asserted moral leadership over the expedition.

But in the months that followed,

some of the Crusades' leaders became increasingly greedy

for power and plunder.

Bohemond remained to rule Antioch,

and instead of driving on to Jerusalem, the expedition's holy goal,

Raymond insisted on pursuing further conquests in Syria and Lebanon.

For many Christians, these delays were unforgivable.

Some even began to question the authenticity of the Holy Lance,

and the integrity of the increasingly delusional fanatic who had found it.

Facing a barrage of criticism, Peter Bartholomew actually begged

to undergo a potentially lethal trial by ordeal,

all to prove his own innocence and the authenticity of the Holy Lance.

On 10th April 1099,

outside the city of Arqa in Lebanon,

the peasant visionary began to prepare for a dramatic trial,

the outcome of which would determine the fate of the First Crusade.

Peter spent the next four days fasting to purify his soul

and then on Good Friday,

olive branches were stacked into two pyres,

four feet in height and 13 feet in length.

With the two pyres set alight,

wearing a simple tunic and bearing the relic of the Holy Lance,

Peter Bartholomew willingly walked into the heart of the inferno.

Some of Peter Bartholomew's supporters later wrote

that he managed to emerge miraculously from the flames unscathed,

and it was only subsequently that a frenzied crowd mobbed him

and broke the bones of his body,

but a very different story was told by his opponents.

They recorded that he emerged mortally wounded by burns.

One thing's certain. The man who had found the Holy Lance in Antioch

had died within 12 days of his ordeal.

The spell of the Holy Lance was broken,

and, with it, the reputation of Raymond of Toulouse.

It was Godfrey of Bouillon who emerged as the Crusade's new leader,

as after more than ten months of delay the Christians advanced with almost breakneck speed.

Any thoughts of further conquests in Lebanon and Palestine were abandoned.

And just three weeks later,

on Tuesday, 6th June, in the year 1099,

after three years

and more than 2,000 miles,

the First Crusade finally arrived

at the spiritual centre of the Christian cosmos.

Around 90% of those who had set out from Western Europe

had been lost along the way, either to death or desertion.

For those few who managed to make it this far,

the sight long-awaited of Jerusalem must have been incredibly moving.

But it wasn't just because the journey to get here

had been so long and arduous -

it was because this place was the most sacred Christian site on Earth.

It was the place in which Christ had undergone his passion, his life, his death,

and, perhaps most importantly of all, his resurrection.

Many Crusaders believed that if they could conquer this city,

it would become one with the heavenly Jerusalem,

a glorious Christian paradise.

Jerusalem's walls, and the Muslim garrison within,

made it an even bigger obstacle than Antioch.

But for the Crusaders, having come so far,

defeat here was simply unthinkable.

After a frantic six-week siege,

Godfrey of Bouillon made the decisive breakthrough,

breaching the city's inner defences.

On the 15th July, 1099,

the first Crusaders finally achieved their long-cherished dream -

the liberation of Jerusalem.

Surging through these streets in bloodthirsty ravening packs,

they overran the Holy City.

Fuelled by three years of unimaginable strife,

privation and yearning,

they unleashed a rampaging torrent of barbaric and indiscriminate slaughter.

One Crusader joyfully reported "With the fall of Jerusalem,

"one could see many marvellous works.

"Some pagans were mercifully beheaded,

"others pierced by arrows plunged from towers, yet others,

"tortured for a long time, were burnt to death in searing flames".

Piles of heads, hands and feet littered the streets,

and even the soldiers carrying out the killing could hardly bear the stench

rising from the blood lapping at their ankles.

Jews as well as Muslims were butchered.

This was holy war in all its horror.

Many Muslims fled to Jerusalem's most hallowed ground,

revered in Islam as the site of Mohammed's ascent to heaven.

But the Christian warriors went after them,

cutting them down as far as the famous Aqsa Mosque...

..where there was such a massacre

that the Crusaders were wading through their enemies' blood.

The massacre that took place

on the streets of Jerusalem was not simply a feral outpouring of pent-up rage.

Instead, it was a much more calculated and prolonged campaign of killing,

that lasted at least two days.

It left this city awash with blood and strewn with corpses.

In a moment that perfectly encapsulated the Crusade's extraordinary fusion

of violence and faith...

..at sunset on 15th July, 1099,

the Crusaders, still covered in their enemies' blood,

gathered here in the Church of the Holy Sepulchre,

believed to be the site of Christ's death and resurrection,

to give thanks to their God.

For us today, the idea that the first Crusaders

could present themselves as faithful Christians,

even as they carried out acts of butchery

might seem abhorrent, almost incomprehensible.

But if we want to understand the first Crusaders,

then we have to try to see the world as they saw it,

to appreciate that they had a distinctly medieval conception of religion.

All the best eyewitness and contemporary evidence

indicates that they ardently believed in what they were doing,

that for them killing for Christ was itself an act of devotion,

an expression of faith that would open the gates of heaven.

Four years after Pope Urban II delivered his dramatic call to arms,

the First Crusaders had achieved their goal.

Jerusalem was now undeniably in the hands of Western Christians.

The success of the first Crusades stunned Christian Europe,

and it became the most widely-recorded event of the Middle Ages.

Contemporaries saw Jerusalem's seemingly miraculous conquest

as an immutable proof that their God did indeed want them

to embrace the idea of Holy War.

This single moment of Christian triumph

would fuel enthusiasm for the Crusades for centuries to come.

But in the decades and centuries that followed, Islam came to regard

the sack of Jerusalem as the central act of Crusader barbarity and defilement.

The Middle East was now locked into a bitter struggle

that would rage for 200 years,

a conflict in which Muslims would embrace the cause of Jihad,

uniting in pursuit of vengeance and the Holy Land's re-conquest.

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