The colour of their skin differed from all mortals of our habitable world.
For the whole surface of their skin was tinged with green.
To the early medieval mind, the world could appear mysterious, even enchanted.
What should you believe about the dog heads?
Are they descended from Adam's stock?
Or do they have the soul of animals?
Behind the wonder was a faith that the world was divinely ordered.
Every creature in the world is a book or a mirror for us.
But in time, that faith would be shaken by an extraordinary cultural revolution.
A revolution in the way we think,
in the way we analyse the physical world.
And in our experience of other continents and cultures.
The sum of European knowledge
and the Christian belief it was based on,
the way we understand the world,
how it was made and when it came into being,
was about to be transformed.
The world between the 9th and 15th centuries.
Supposedly a period of superstition and ignorance.
Where ideas are stifled by the dead hand of religion.
The intellectual landscape of the Middle Ages is certainly unfamiliar, even strange.
From furious debates about arcane points of theology,
to reported sightings of people with the heads of dogs.
But behind all this strangeness lies a world of passionate enquiry.
There's scholarship, science, intellectual exploration and sophisticated logic.
The world experienced by medieval men and women was very different from our own.
Events that might be called supernatural
occur frequently in medieval records.
At the end of the 12th century, Ralph, the respected abbot of the monastery of Coggeshall,
recorded an extraordinary story involving the capture of a wild man who lived in the sea.
It happened that the fishermen there, fishing out in the sea, caught
a wild man in their nets. They brought him to the castle as a wonder.
He was naked and presented a human appearance in every part of his body.
When taken to church, he showed no signs of reverence or belief,
however often he saw holy things.
He did not wish to utter a word, even when hung by the feet and subject to dire and frequent torture.
MOANING
What's striking to us today about this strange and rather sad tale
is that the abbot is less concerned to determine whether the story is true...
than to work out exactly what category of creature this might be.
Was he a mortal man, he asked, or some fish in human form?
Or a wicked spirit lurking in the body of a drowned man?
HOWLING
The wild man eventually escaped back to the sea.
His tormentors, and Ralph of Coggeshall,
are left wondering what kind of creature this was, and were there others like him sharing their world?
Medieval records are brimful of stories of sightings of strange creatures.
She had come from an underground world where the inhabitants
were as green as grass and never saw the sun, but were lit by a twilight glow.
During the reign of Henry II, a servant called Richard from North Sunderland met with three young men
dressed in green on green horses, who carried him off to a lofty mansion.
Here they ate oaten bread and drank milk.
These stories were not regarded as folklore,
but as reported, substantiated facts.
The chronicler, Gervase of Tilbury, in the 12th century, reported hundreds of such sightings.
One concerned the congregation of a Norfolk church, who saw an anchor hanging from the sky.
The anchor was caught on a tombstone.
Attached to it, and leading up into the clouds, was a heavy chain.
All of a sudden, a sailor appeared from the cloud
climbing down the chain hand by hand, using the same technique as we do.
He was seized by the churchgoers.
The other world sailor suffocated by the moistness of our denser air and died in their grasp.
CROWD CHATTER
He was human enough to sail a ship, but could breathe only the air above the clouds.
What kind of being was he?
Confounded by the sheer number of such discoveries,
medieval thinkers turned to the most authoritative guides they had -
the Bible and the teachings of the Church.
According to medieval thinking, all living things belonged
to one of three categories - animals, humans and spirit beings.
That is, angels and demons.
The creatures described by Gervase of Tilbury appear to defy all three categories.
If the beings who appeared on our doorstep seemed strange,
the world beyond the shores of Britain were stranger still.
A sense of just how enchanted it was can be found amongst the treasures of Hereford Cathedral.
This is the Hereford Mappa Mundi, which means map of the world.
It was produced around about 1300 and it's one of the oldest, biggest and most elaborate depictions
of the physical earth to have survived from the Middle Ages.
It was made from the skin of a single calf.
The head would have been here, the tail here, the forelegs.
And what it shows is the three continents known to medieval geography.
East was at the top.
Here was Asia,
Africa and Europe.
And in the centre, symbolically, was the City of Jerusalem.
Many towns and cities, rivers and seas are accurately marked.
Here, the Red Sea has been given a very literal interpretation.
But understanding the geography of the world was not the sole point of such maps.
This map was certainly not designed to get you from A to B.
But it does show how people at the time pictured the earth
on the basis of the information available to them.
It's covered with drawings.
Some of them rather familiar.
Russia is represented by a bear.
Norway by a man on skis.
The map is labelled as a history, or story,
and it does seem to depict time as well as space.
Above Jerusalem, the crucifixion is taking place.
Out here we have the Golden Fleece.
And at the top Adam and Eve are being expelled
from the Garden of Eden.
Above them we see the future.
The Last Judgment.
The souls here are being received by God the Father.
While the damned are being led off to the mouth of hell.
The observable world and the world of divine revelation,
the natural and the supernatural coexist quite comfortably.
In Europe, many well-known cities are represented,
including the most important - Rome, Paris, St Andrews.
But as one moves further away from Europe, the world becomes stranger and there are stranger creatures.
Mermaids.
Unicorns.
Men with their faces in their chests.
The monopods - Creatures with one giant foot,
that when they lay backwards, they could use as an umbrella.
HOWLING
The further away we get from the familiar world around us,
the more exotic and fantastic creatures become.
HOWLING
This was not just some fanciful imagining by the map's creator.
These creatures were known to have lived in far off lands.
And they presented the medieval thinker with some really pressing questions.
What kind of creature were they, and how should you deal with them?
BLEATING
Somewhere on the fringes of the world lived a race of dog-headed men.
Such creatures appear quite frequently in medieval texts and illustrations.
These beings appeared to be human in most respects, except that they had the heads of dogs.
The question was, did they have the souls of humans?
This was a practical concern for missionaries.
If they encountered dog-heads, should they preach to them or not?
After all, it made no sense to preach to animals, but it was every Christian's duty
to convert human souls to Christ,
however bizarre the body in which that human soul was encased.
Just such a question puzzled a young missionary in the 9th century as he prepared for a trip to Scandinavia.
He sought the advice of a leading scholar of the time, named Ratramnus.
What should you believe about the dog-heads?
Are they descended from Adam's stock, or do they have the soul of animals?
Ratramnus's advice is very revealing.
First he asserts that if the dog-heads are descended from Adam they are certainly human.
Admittedly, the shape of their heads and their barking are against them.
But nevertheless, they show many crucial human attributes.
They lived in villages.
They farmed the land and kept domesticated animals.
Moreover, the fact that the dog-heads cover their genitalia
is a sign of their decency,
which in turn means they have the power of judging between the decent and the indecent.
For the scholar Ratramnus, this is a powerful point.
I do not see how this could be
if they had an animal and not a rational soul.
For no-one can blush at indecency unless they have a certain recognition of decency.
A group of moral, rational beings living in a society bound by laws,
this is humanity, not mere animality.
Therefore, he concludes, dog-heads were in essence human beings.
Some reportedly adopted Christianity.
One even became a saint.
According to some, St Christopher, the patron saint of travellers, was one such creature.
There were of course no eyewitness accounts of these creatures and they were never seen in Britain.
It is in fact the very nature of a dog-head always to be somewhere else.
It's easy to poke fun at this earnest philosophising
about such bizarre creatures as dog-heads and fish-men and people who come down from the sky.
But such debates were pursued with keen logic and an impressive spirit of dedication.
Logic and observation were the tools whereby things were made to find
their place in a world view that was intensely religious.
And the fit was not always a neat one.
THUNDER CRACKS
For much of the Middle Ages, people believed things that today might strike us as paradoxical.
To the medieval mind, an event could be both natural AND supernatural.
The great Ecclesiastic, Hrabanus Maurus,
recorded how people reacted to an eclipse in the 9th century.
I saw people shooting spears and arrows at the moon,
or scattering the fires from their hearths into the air.
I heard the bellowing of warlike horns.
The moon, the people said, was being attacked by monsters,
and unless they brought help, the monsters would devour her.
But it wasn't only the ignorant who reacted in this way.
Amongst scholars, too, it was widely believed that eclipses meant something.
They signified divine intervention of some kind.
In fact, a common medieval term for an eclipse was "signum" - a sign.
It would be wrong to regard the interpretation of eclipses as divine signs,
as stemming from ignorance of their physical causes.
Here is Isidore of Seville, the great encyclopaedist of the early Middle Ages.
He knew exactly what was happening.
The moon suffers an eclipse
if the shadow of the earth comes between it and the sun.
The sun suffers an eclipse when the new moon is in line with the sun
and obstructs and obscures it.
He was, of course, right.
So were eclipses divine messages or natural phenomena?
They were both.
The two explanations could coexist.
HORSES BRAY AND CARTS CLATTER
In 1218, Oliver of Paderbon, a chronicler at the time, described
how troops on the march saw a favourable sign in the night sky.
Soon after we arrived, there was an almost total eclipse of the moon.
This often happens from natural causes at the time of the full moon.
Nevertheless, since the Lord says, there shall be signs in the sun
and in the moon, we interpreted this eclipse as unfavourable to the enemy.
The eclipse was interpreted as a sign from God,
even though its natural cause was also recognised.
The ability to understand perfectly well the physical processes of an event like an eclipse,
while remaining convinced of its religious significance, is a classic feature of medieval thinking.
What has been called "The Disenchantment of the World" was only just beginning.
Physical laws and divine agency were yet to quarrel.
In the medieval world view,
the desire to understand burned with a moral intensity.
In the early Middle Ages, the quest for knowledge was largely confined
within the walls of the great monasteries and cathedrals.
Learning stayed in the hands of monks and priests, quite literally.
Medieval Europe was a manuscript culture, which means that for a text
to exist at all, it had to be copied out by hand.
And for it to exist in more than one copy, it had to be copied out again.
And again.
It was a slow and laborious business.
Occasionally, a small voice of protest can be heard from the margins.
Here ends the second part of the Summa Theologica.
Very long, very verbose and very tedious to write out.
Thank God. Thank God and again, thank God.
Books were consequently extremely valuable and highly treasured.
If they travelled at all,
it was usually from one monastery to another. And if they got lost?
Well, at least one medieval librarian was not going to be happy.
For him that steals this book or borrows it and does not return it,
let it change into a serpent in his hand and rend him.
Let him be struck with palsy and all his limbs blasted.
Let him languish in pain, crying aloud for mercy.
And when at last he goes to his final punishment,
let the flames of hell consume him for ever.
Books were rare, precious.
Available only to the few.
At the beginning of the Middle Ages, learning was locked away in the hands of monks and priests.
They were the interpreters of the world.
Learning was not something to be disseminated, so much as jealously controlled.
For knowledge existed not for its own sake,
but as part of the search for religious truth.
In the Library of Gonville and Caius College in Cambridge
are medieval manuscripts which describe animals and nature.
What we have here are medieval accounts of the natural world.
A world of animals, a world of birds,
a world of fish.
Systematically arranged
and often beautifully and lavishly illustrated.
They're called bestiaries.
And they give us an insight into how people in the Middle Ages responded to the natural world around them.
Medieval thinkers cared less about what an animal looked like,
or where it lived, than about what its nature and character
could tell us about God's plan for mankind.
Take the story of the beaver.
The beaver, the bestiary tells us, is hunted for its testicles.
It does indeed secrete valuable musk in that region.
When the beaver sees the huntsmen coming, it cuts off its own testicles with its teeth,
then waves its leg, showing the huntsman that it has nothing for him.
In just this way, says the bestiary, we must cut away vice from ourselves,
so that when the Devil comes after us, we can show him that we have nothing for him.
The world had been created by God in the same way that a book is written by its author.
The bestiary texts often begin with a large illustration
of Adam giving names to the animals.
They've assembled in a rather charming way to hear what they're going to be called.
And it's very symbolic, because in the medieval period,
the natural world was not viewed as something independent in its own right.
It had been created for human beings.
But whether the creatures are fabulous or realistic,
whether the bird is a phoenix or a blackbird,
the purpose of the bestiary was not really to act as a kind of field guide.
Its purpose was to tell you what these creatures meant.
They had a message for human beings, and the message was moral and spiritual.
A similar warning against the wiles of the Devil
can be found in the story of the whale,
illustrated in this other bestiary in a rather spectacular drawing,
in which we see the sailors
that have come to what they think is an island in the sea.
They land, they hammer in a stake to anchor their ship,
they light a fire.
What they haven't realised
is that the island is in fact the hump of a giant whale,
which is immediately to suck them down into the depths of the sea.
That's a warning for us to be on our guard against the wiles of the Devil and his deceptions at all times.
According to the philosopher Alan de Lille,
every creature in the world is a book or a picture or a mirror for us.
But this view of the earth as a sacred book was beginning to be undermined
by changes taking place in the medieval world.
The growth of towns all over Europe.
The upheavals of war.
The new horizons opened up by trade.
The growing complexity of government and law.
The bureaucracy required to run a medieval state was growing more sophisticated.
Where were the lawyers and administrators to come from?
A new class of man, educated in a different way, was needed.
A background in biblical scholarship was no longer enough.
Tutors began to congregate in Oxford in the mid-12th century.
They offered teaching in law and other secular subjects in return for money,
setting themselves up in rented rooms.
This was a small revolution.
You could now pursue a career in learning without being a monk or a priest.
Young boys began to study, not necessarily to become closer to God,
but to increase their chances in life.
Hundreds of teenage boys living away from home in a strange place,
renting rooms, buying food, going to the pub, interested in girls.
In other words, a recipe for trouble.
In 1209, the body of a local woman was discovered in Oxford.
She was last seen drinking with a student in a nearby tavern.
The suspect could not be found.
In revenge, the student's three roommates
were arrested by the town's authorities and were all hanged.
Enraged by the injustice, almost the entire body of students and teachers upped and left.
It was to be five years before they returned.
In 1214, formal university regulations were drawn up.
A Chancellor was appointed
and a syllabus was introduced with exams at the end.
The British university, as we know it today, was born.
And as for the teachers who fled from Oxford?
Many made their way to the City of Cambridge
and established a rival university.
The university is one of the great legacies of the medieval world.
In time, rich patrons, even kings, endowed new colleges.
The town of Cambridge was transformed from a crowded little river port
into one of the wonders of the world.
What was taught differed from the kind of learning
that had been enclosed in the great monasteries of Europe.
Science, philosophy, logic, mathematics...
And with it, came a new kind of scholar.
Men like Peter Abelard at the University of Paris,
who saw himself as a warrior for truth.
I preferred the weapons of logic to all the other teachings of philosophy
and armed with these,
I chose the conflicts of disputation instead of the trophies of war.
His critical and analytical approach typifies the new intellectual style
that arose in the 12th and 13th centuries.
As he wrote, "By doubting we come to inquiring,
"and by inquiring, we perceive the truth."
This hunger for a different kind of understanding was to threaten the monastic monopoly of learning.
Upheaval in the wider world accelerated this intellectual shift.
Christian Europe was on the offensive.
Its knights conquering lands all around the Mediterranean.
In the 11th and 12th centuries,
the Christians of Spain were pushing south, seizing Muslim territory.
In 1085, they conquered the great City of Toledo.
This fortified city had been a great cultural centre of Islamic arts and science.
It was a major prize for the Christian armies.
Within its walls were wonderful libraries.
They contained ancient Greek texts translated into Arabic,
including the scientific works of the great philosopher, Aristotle,
which had been unknown in the West until that time.
Word of these discoveries began to spread across Europe,
even reaching the ears of ordinary clerics in Britain.
In 1170 or so, a Norfolk priest, Daniel of Morley,
heard stories about the manuscripts that had been discovered in the libraries of Spain.
Frustrated by what he saw as the limited intellectual world around him,
he prepared to make the long journey to southern Europe.
Daniel was impatient with the traditional learning
that seemed devoted to minute annotations of texts of Roman law.
What excited him was the advanced study of mathematics, geometry and astronomy.
Scientific subjects were celebrated especially in Toledo.
I hasten there to learn from the world's wisest philosophers.
In Toledo, he found what he was looking for.
Never before had Christian scholars had access to such a flood of new information.
Men like Daniel of Morley helped start an intellectual revolution.
In Daniel's baggage on his way back from Spain were scientific works
by non-Christian authors like the great Muslim scientist, Abu Ma'shar,
and by pre-Christian authors like Aristotle.
As Daniel himself said,
he was "returning to England with a valuable load of books."
The journey from Toledo to Norfolk was just the latest part
of an extraordinary intellectual voyage.
Ideas travelling over centuries and across continents.
Aristotle's Metaphysics.
Aristotle's Physics.
Aristotle's book on animals.
These texts had undergone an amazing journey before they became available to the scholars of medieval Europe.
Written originally in the 4th century BC, in Ancient Greece,
they'd spread throughout the Greek world.
Then, many centuries later with the rise of Islam and the spread of the Arab Empire,
they'd become familiar to Muslim scholars who had translated them in to Arabic.
They then spread throughout the Islamic world, including Spain.
And there, in the 12th century, in this multi-cultural, multi-lingual society,
scholars came from England, from Paris, from Italy, to seek them out
and to translate them into Latin - the universal language of education in western Europe.
And then, at last, these texts, after 1,500 years,
could spread into the intellectual centres of the West.
They were to cause a shock wave.
Up until now, the foundations of medieval philosophy had been built
upon the Bible and a thousand years of Christian teaching.
God had created the world in seven days and had power over all things in it.
The Greek philosophers started from completely different assumptions.
The ideas of the classical Greek thinkers, such as Aristotle,
written four centuries before Christ, obviously took no account of the idea of the Christian God.
They debated human psychology with no reference to Christianity
and of course, there was no biblical revelation, no creation in seven days.
Instead, they argued that the universe had always existed and would always exist.
The works of Aristotle, along with the other Greek and Arabic thinkers,
presented the Christian west with something entirely new.
A rational, systematic analysis of the universe based on principles that were non-Christian.
A picture of the world based on nature and reason alone.
The response of the Church authorities could have been predicted.
The books of Aristotle on natural philosophy
and the commentaries on them, shall not be read at Paris,
in public or in private, under pain of excommunication.
MONKS CHANT
Worse still, if there are natural laws that govern the universe,
that would seem to imply that God is their prisoner.
To some, such thinking seemed nothing short of heresy.
CHANTING
Religious belief seemed to be on a collision course
with rational theories about the nature of the world.
It would take a remarkable Dominican friar to reconcile the apparently irreconcilable.
Thomas Aquinas came from an aristocratic family in southern Italy.
He was a studious boy and his family seem to have had quite specific ambitions for him.
They thought it would be rather fine if he became Abbot
of the nearby and fabulously wealthy monastery of Monte Cassino.
But Thomas had other ideas.
He was attracted by the newly founded Dominican Order,
which promised poverty, preaching and teaching.
His family were outraged at this wayward behaviour.
They tried everything they could do to break his resolve.
They even locked him up and sent seductive young women to visit him.
But he persevered and set off as a Dominican to Paris, the heart of the intellectual life of western Europe.
There, Aquinas encountered the ideas of Aristotle.
He realised that the Church had either to accommodate Aristotle, or be overwhelmed by him.
Human reasoning, Aquinas argued, derives from God.
Christian revelation also derives from God.
If human reason was used correctly,
it could not contradict what God had revealed in the Bible.
Had the universe always existed, or did it have a beginning?
Aquinas argued that this could neither be proved nor disproved by reason alone.
Aristotle had gone as far as possible with reason.
Only divine revelation could give us the truth here.
In his huge work, the Summa Theological,
Aquinas laid out every conceivable argument between the two ways of thinking.
Aquinas had pulled off a Herculean task of scholarship.
So intense was the experience, it took a heavy toll on both mind and body.
Compared to the great glory of God,
my writing is like straw.
He died, leaving the Summa unfinished.
But his ideas lived on.
The use of reason, based on Aristotle,
to strengthen Christian thinking, came to be known as Scholasticism.
No question was too difficult, or too obscure.
Indeed, the period was to become so celebrated, or notorious, for intense theological inquiry,
that medieval thinkers are often said to have wrestled with the burning question,
"How many angels can dance on the head of a pin?"
In fact, this isn't a genuine piece of medieval head scratching,
but a Victorian pastiche of it.
But it's not without a grain of truth.
Tomas Aquinas did speculate whether angels, who of course have no bodies in the usual sense,
could occupy more than one space at the same time, or whether many of them could be in the same space.
It's the medieval equivalent of the kind of question asked today
in quantum physics - can something be in two places at once?
But the point is this, if you know that angels exist because religious revelation tells you so,
it makes sense to use your intellect and reason to ask what they are like.
Where they can go, what they can do.
In that sense, it's a perfectly rational question.
Early medieval thinkers had marvelled at eclipses, fish people and men from the sky.
Their later successors were more sophisticated.
Their mastery of rational debate provided them with the tools
to understand a flood of new information and knowledge
that poured into western Europe during the 12th and 13th centuries.
Contact with the Arab world brought more than an introduction to Aristotle.
What the Muslims excelled in was science,
and medieval intellectuals were dazzled by their learning.
Arabic words suddenly appeared in scientific language.
Algebra, alchemy - the earliest form of chemistry.
Alcohol, as a laboratory substance,
and the star names like Aldebaran and Algol.
And perhaps the most significant import of all, Arabic numerals.
If you try doing calculations with Roman numerals,
you'll understand why.
Knowledge had advanced perhaps a thousand years in just a century.
The stage was set for a man who has been called
the father of modern science - The Franciscan friar, Roger Bacon.
Inspired by Muslim philosophers, Bacon grasped the importance
of testing accepted arguments with controlled experiments.
The strongest arguments prove nothing so long as the conclusions are not verified by experience.
"All things must be verified by the path of experience," Roger Bacon wrote.
"Experiments on a large scale with instruments are required."
"Experimental science teaches how wonderful instruments can be made."
Bacon was especially fascinated by light.
Indeed, he thought that the light emitted by objects
was the key to understanding the universe.
Everything that has actual existence in the world of the elements,
sends out rays in every direction.
He questioned why a candle appeared to be upside down
when observed through water.
He recognised that a rainbow was not a physical object,
but an effect of light on the eye.
There are as many rainbows as there are observers.
He could even create a rainbow in his laboratory.
He understood its geometry
and calculated the maximum height it could appear in the sky.
Slowly but surely, the world was being disenchanted,
from a creation sustained by divine will, to one which followed its own natural laws.
And human beings too, he thought, are governed by such laws.
This was more than the Church was willing to accept.
In 1277, his ideas were condemned as "suspect novelties"
and he was imprisoned.
Bacon dreamed of what would be possible in the modern world of science.
Machines for navigation can be made without rowers.
Carriages can be made that are moved without animals.
Flying machines,
and machines for walking in the sea - even to the bottom.
Bacon's vision of a technological future clearly signals
a radical shift that was to occur in our attitude to the physical world.
From awed contemplation, to a sense of mastery.
Slowly but surely, the world was being observed,
analysed and measured.
To measure events in the physical world
called for a more sophisticated measurement of time itself.
In the early Middle Ages,
time was measured simply by irregular points in the day.
Meals, church services, high and low tides.
Accurate mechanical clocks were essential to standardise its measurement.
Islamic technologies had demonstrated precision engineering.
But as Robert the Englishman documented in 1271,
in order to make a clock, an apparently insurmountable problem had to be resolved.
Clockmakers are trying to make a wheel
which will make one complete revolution in each day.
But they cannot quite perfect their work.
What prevented them perfecting their work
was the absence of a device to allow the wheel to turn in precisely equal movements.
In technical terms, an escapement.
As the 13th century drew to a close, rich abbeys and cathedrals
gave huge resources of money to the inventing of an accurate clock.
This is the mechanism of the Wells Cathedral clock,
now in the Science Museum in London.
It's one of the oldest surviving mechanical clocks in the world.
Although some parts of it are later, like the pendulum,
added in the 17th century, the heart of it is over 700 years old.
And it's a magnificent witness to the skill and ingenuity
of the medieval clockmaker's art,
solving all those problems outlined by Robert the Englishman.
At first, mechanical clocks merely rang a bell every hour.
But this clock, when in situ in Wells Cathedral,
was given a face and some ingenious entertainment.
Now hours, minutes, seconds, could be observed and standardised.
Something as abstract as time itself could now be seen and measured.
Clocks gave an entire new way of thinking.
Things could go like clockwork.
And in the long run, it meant that state bureaucracies could run more efficiently,
and, in science, that rates of reactions could be measured.
Medieval Europe was becoming a powerful centre of new science and technology.
The great churches and cathedrals became more ambitious
in their design and engineering,
reaching higher and higher towards heaven.
Warfare demanded deadlier, more advanced weaponry.
And in Italy, the first semblance of a banking system was being set up to fund vigorous international trade.
But there was a surprise in store for these sophisticated Europeans.
An unimaginably advanced world was about to be opened up to them.
Our understanding of the physical world in which we live,
and also who we shared it with, was about to be radically transformed.
And some of the most cherished notions of medieval knowledge would also be put to the test.
The conquest of one third of the known world by Genghis Khan
and his Mongol successors in the 13th century
provided a unique opportunity.
As the dust settled on the vast new empire,
it provided a gateway to Asia.
It was now possible to travel relatively securely from one end of Eurasia to the other,
from western Europe to the heart of China.
The great age of medieval world travel was about to begin.
In 1253, a Franciscan friar, William of Rubruck, was amongst
the first Europeans to reach the Mongol capital of Karakorum.
We came among the Mongols
and it truly seemed to me that I had entered another world.
He hoped to meet the strange creatures described in the Hereford Mappa Mundi.
The monopods and unicorns.
But they were nowhere to be found.
I asked about the monsters, or human monstrosities,
of which the scholars speak.
They told me they had never seen such, which astonished me greatly, if it be true.
On the contrary, it appeared that the people of the East
thought that dog-heads lived in the West.
Wherever the travellers went asking for them, they encountered people who said,
"What? We thought they lived where YOU came from."
Other Europeans soon followed to continue the quest.
John de Marignolis was sent by the Pope.
I was hunting for the monstrous races described in the old literature.
The one-eyed people.
The hermaphrodites and the dog-heads.
It was becoming clear that the monsters lived just over the horizon.
As the horizon was pushed back, so the myths receded.
A long-standing puzzle of whether or not to preach to dog-heads
or monopods was solved by the absence of those creatures.
So what was out there beyond Europe?
A world more extraordinary
than anything the medieval mind had imagined.
In 1270, the 17-year-old son of an Italian merchant
left his native city of Venice for China.
Marco Polo was not to return for 25 years.
His epic odyssey brought him fame, lasting even to this day.
On his return to Europe, he wrote a book describing his journeys.
The Travels Of Marco Polo.
It caused a sensation.
It contained reports of stunning civilisations,
far in advance of our own.
Wild and dangerous landscapes unlike anything in Europe
and tales of survival that beggared belief.
The desert is so long
that it would take a year to go from end to end.
It consists entirely of mountains and sand and valleys.
There is nothing at all to eat.
Marco Polo's account of the palaces of the East
described unimaginable wealth and power.
The walls of the halls and chambers are all covered in gold and silver.
The hall alone is so vast and so wide
that a meal might well be served for more than 6,000 men.
When he was on his deathbed, Marco Polo's friends came to him and said,
"Now is your last chance to correct all those falsehoods you put in the book."
He looked up at them and said,
"I haven't told half of what I actually saw."
Merchants and missionaries streamed into China.
The Silk Road took travellers from the Mediterranean
to the East China Sea, allowing exchange of ideas, goods and technology.
Then all this came to a sudden end.
With the collapse of the Mongols in 1368,
the route to the East was closed.
But the West was hungry to renew contact with the East,
drawn to the riches and exotic places it knew existed there.
Another route had to be found.
One Italian sailor became obsessed with Marco Polo's book.
He carried it around with him and he made little marginal notes on it.
His name was Christopher Columbus.
Columbus had studied maps like the Hereford Mappa Mundi.
He'd read the Bible carefully,
for hints about the geography of the earth.
But he had a more radical idea.
He was determined to seek the fabulous East by sailing West.
Columbus' accidental discovery of America shrank the world.
It was a watershed in the history of medieval Europe.
The moment when new horizons opened,
and the start of a new era in the meeting of cultures.
Columbus' voyage of 1492,
marked the beginning of the process of globalisation
and European colonisation that has created the world we live in today.
But when Columbus sailed the ocean, he did so with a very medieval mind.
He thought he had reached the fabulous East described by Marco Polo.
Like other travellers, he believed he would meet strange races.
Cannibals, amazons, dog-heads.
And in South America,
he believed he had found the biblical Garden of Eden.
I am firmly convinced that the earthly paradise truly lies here.
Columbus' voyage to America marks the end of the medieval age
and the birth of the modern one.
A new period of discovery and expansion
and conquest was about to begin.
The disenchantment of the world was nearly complete.
Early medieval men and women saw the earth as divinely created and ordered.
Its workings were beyond their control.
For their modern successors, armed with new technologies,
from the compass to improved sailing ships, to gunpowder,
it was a place to be mastered, exploited.
In more ways than one, it was the discovery of a new world.
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