[ominous music playing]
[music intensifies]
[slicing sound]
[gasps, pants]
[narrator] In 39 A.D.,
Caligula is one of the most powerful men in the world.
But he will come to be known
as Rome's mad emperor.
[theme music playing]
[narrator] In just over a century, the Roman Empire has doubled in size.
Now stretching nearly two million square miles
from the Atlantic Ocean to Egypt.
The city of Rome is rapidly expanding,
[Tom Holland] Rome was an enormous city,
even by the standards of today.
And there was a sense in which
infrastructure had been key to its growth, right from the very beginning.
And the engineering feat was
indeed formidable.
[narrator] Roadways now connect Rome to places like Northern Africa,
modern-day France, and Spain.
And advancements in design, like aqueducts...
sewer systems...
and amphitheaters...
have turned Rome into one of the most
advanced civilizations on the planet.
[Mike Duncan] Rome was as powerful as it had ever been,
and was continuing to grow in power.
They were at the zenith of their power.
So...
when it came to its position
relative to other foreign powers, Rome was the biggest power in the world.
[narrator] Rome's rise to global dominance
is in part thanks to its powerful military,
made up of nearly 300,000 soldiers.
The Roman military dominated the Western world.
There was nothing to match the Roman military.
[narrator] The Roman army has been waging a war against barbarians in Germania,
hoping to keep their borders secure.
[screaming]
Rome has spent years and years fighting on the German frontier,
to ensure that the German tribes were not able to come and march into Gaul
or into other parts of the Empire.
So it's a very big operation.
[man] Here, take this.
Hold it high and strong.
Feet apart.
[narrator] On the sidelines of the battlefield...
One, two...
...a young Caligula is growing up.
For the first years of his life,
Caligula was pretty much on the road,
going from military camp to military camp.
His playground was, effectively, the most violent arena of war.
Caligula is brought up in a household of great privilege, great expectations.
Because he was the son of a great general.
And not only was his father a great general,
a man of honor, but he was the nephew of the ruling emperor of Rome.
[narrator] Caligula's father is the most beloved leader in the Roman army,
and next in line to become emperor of Rome.
His name is Germanicus.
[Germanicus] How many men to a cohort?
Four hundred and eighty.
How many to a legion?
One thousand. Five thousand.
Led by?
Six tribunes...
[Amanda Ruggeri] Germanicus was a blue-blooded Roman prince.
The guy was handsome, he was charming,
he was well-educated.
[Amanda Ruggeri] He was, at the time, the most respected general in Rome.
So Caligula as a child would have been growing up
as the son of this incredibly popular guy,
and he is traveling around with his father
all throughout his young childhood.
Are you tired, or should we move onto weapons?
Weapons.
-Javelins are made of... -Wood and iron.
-Short swords? -Steel.
[narrator] Germanicus trains Caligula to be a great warrior,
forming a close bond between father and son,
but that's all about to change.
While Germanicus protects Rome's borders,
nearly a thousand miles away,
the reigning emperor, Tiberius, works to protect his legacy.
Tiberius was not a natural politician.
Anything but.
He was charmless in many ways,
he had many enemies,
he clashed with the Senate.
He ended up leading the trial and execution of numerous senators.
Under Tiberius, Rome underwent a reign of terror.
[narrator] Tiberius is only the second emperor Rome has ever had,
but he spends much of his reign in the shadow of his predecessor.
[crowd cheering]
[Adrian Murdoch] The previous emperor, Augustus,
was the greatest emperor that Rome ever had.
He managed to do the impossible.
He brought Rome together,
he brought the provinces together,
but on the other hand, the emperor Tiberius was the emperor of austerity.
There was none of the glamour of Augustus,
he didn't want to push the Empire forward.
[indistinct chatter]
[narrator] Caligula's father, Germanicus,
may be next in line to be emperor of Rome...
[inaudible whispers]
...but Tiberius wants to pass on the throne to his son.
So he makes a move to take out Germanicus.
[soldier] Guards!
[ominous music playing]
[soldier 1] Don't touch him.
[soldier 2] What happened?
[narrator] Caligula is only seven years old
when his father dies suddenly,
leaving him, his two brothers, and three sisters without a father.
And the Roman Empire
with no designated successor to the throne.
Germanicus, Caligula's father, was very, very popular,
and he's often regarded as the greatest emperor that Rome never had.
When Caligula's father died, life became a lot less comfortable.
It doesn't take a professional psychologist to realize
quite what a damaged boy Caligula must have been.
[narrator] After his sudden death,
the family of Germanicus is convinced that he was poisoned.
[Anthony Everitt] His wife, Agrippina, was enraged,
and she was convinced that the emperor had assassinated
her much-loved husband, and she wouldn't keep quiet.
[indistinct chatter]
Caligula's mother was a master of mobilizing public opinion.
[Corey Brennan] One of the things that she did
was she worked Rome into hysteria
after the alleged murder of her husband, Germanicus.
And, in fact, she was viewed as very dangerous.
[chattering]
[narrator] With Agrippina spreading word that Germanicus has been murdered,
the people of Rome begin to turn on their emperor.
[man] I've already paid off servants in their household.
They'll testify they heard the sons commit treason.
Once the Senate finds them guilty...
We'll have them executed.
Imprisoned
is what I was going to suggest.
It'll lessen suspicion, and as their uncle you'll appear merciful.
Shall I move forward?
Yes.
[narrator] Fearing a revolt,
Tiberius knows he has no choice
but to keep Agrippina quiet.
[Caitlin Gillespie] Tiberius felt threatened by Germanicus' family,
who was regarded as the better heirs
to the throne than the family of Tiberius himself.
And Agrippina gained pity over their family for his premature death.
[indistinct chatter]
-[loud thud] -[soldiers clamor]
[Agrippina] Run! Run!
There's a third son.
Find him.
He's not here.
Where is he?
[heavy breathing]
[Agrippina whimpers]
[man] Take her, too.
[gasps]
[music intensifies]
[narrator] Caligula's mother and older brothers
are rounded up by imperial guards,
and subjected to one of Tiberius' most infamous policies,
the treason trials.
If you had to put your finger on just one aspect of Tiberius' reign
which made him more unpopular than any other one,
it was the treason trials, which was anyone who criticized the emperor,
even verbal insults, not diminishing the state or treason to the state,
but just any criticism of the emperor was punishable in a court of law.
This is how Caligula's entire family was eliminated.
Caligula's mother was sent into exile.
His older brother was imprisoned and his other brother was executed.
All because, essentially, they are seen as potential threats to Tiberius.
[narrator] Caligula and his three younger sisters are sent to live with their grandmother,
under the close watch of Tiberius' soldiers,
never sure when the emperor will decide to eliminate them.
It's hard to work out quite what a difficult childhood Caligula must've had.
In one sense, he was a marked man at every stage.
His father was dead,
he was being kept effectively under house arrest in Rome.
So he will have grown up his entire life thinking,
"At midnight, there could be a knock on the door,
and someone with a knife could kill me."
[intense music playing]
[narrator] As he grows into a young man,
Caligula manages to keep his distance from Tiberius.
But an unexpected death
is about to bring him face-to-face with the emperor.
In 23 A.D.,
Drusus, Tiberius' son,
dies suddenly, at the age of 35.
Drusus was the next in line
to assume the throne.
And after Drusus' death,
Tiberius was shocked to the core.
There's not much new to report.
But there is a grumbling
about who now is to be considered the next in line.
I know this is difficult,
but it's time to start thinking about naming a new successor.
I'd be willing to step into that role if you decide it's necessary.
[suspenseful music playing]
Let me think about it.
[scoffs]
[narrator] While the cause of death is unclear,
there's only one man who will benefit from Drusus' demise,
the head of the Praetorian Guard...
Sejanus.
[Aaron Irvin] Sejanus presented himself
as nothing more than a loyal ally and servant of Tiberius.
And he did so through cultivating a friendship,
a personal relationship with Tiberius,
but he was far more ambitious than perhaps Tiberius had in mind.
It took Tiberius completely by surprise.
He had never, it seems, expected that Sejanus would be capable
of such a betrayal.
[narrator] With his son dead,
and no one left to trust,
Tiberius begins to grow paranoid of everyone around him
and decides he needs to get out of Rome.
[intense music playing]
Anybody would've been paranoid in the emperor's palace at this stage.
So Tiberius puts himself into a self-imposed exile
on the Island of Capri.
And he never sets foot in Rome again, for the rest of his life.
[narrator] Tiberius works quickly to select a new successor.
Caligula.
Find him.
Bring him to me.
Macro.
Tell no one.
Tiberius needed an heir because the Empire needed an emperor.
The Empire needed somebody at the top,
and after Drusus' death,
and the removal of the children of Germanicus apart from Caligula,
Caligula was the only person to fit the bill.
[narrator] Now out of Rome,
Tiberius hides out in his luxurious villa on Capri.
Located in the Tyrrhenian Sea,
Capri is over 100 miles removed from Rome,
leaving Tiberius completely isolated from the Empire he runs.
[Barry Strauss] Tiberius lived in a villa modestly called the Villa Jovis,
"the Villa of Jupiter,"
as if Tiberius was some sort of god.
This villa is perched at the edge of a cliff at one end of the island,
it's a very beautiful and dramatic spot.
And Tiberius engaged in a life of great decadence.
[narrator] Once settled in Capri,
Tiberius has full control over who may enter the island,
and spends the next few years
taking advantage of his newfound privacy,
by indulging in an excessive lifestyle.
The decadence was quite spectacular on Capri.
There was the finest food, there was the finest wines,
there were the most beautiful prostitutes.
It was a very open and free lifestyle,
but it became quite debauched, on every possible level.
The stories that we hear coming out of Capri are very much a reflection
of how much the Roman people disliked Tiberius.
In these stories, he is presented as weird and bizarre.
He watches people have sex around him in various and sundry ways.
For a 12-year period,
Caligula's life was filled with watching his closest family members become exiled
and killed for speaking out against Tiberius.
So in 31 A.D. when Caligula was called to the Island of Capri,
we can only imagine the fear,
the apprehension that he must have felt at that time.
[guard] This is the son of Germanicus.
Is that true?
Yes.
You blame me for your father's death, don't you?
Your mother always did.
So you've spent your entire life believing that I was the one responsible.
I didn't kill your father.
He did.
[Tiberius] This is the man responsible for your father's murder.
The man who poisoned my son.
[grunts]
[choking noises]
Sejanus thought himself worthy of the throne.
So, one by one,
he got rid of everyone who stood in his path.
I am not the man you think I am.
See him to his room.
[intense music playing]
Certainly, that early relationship between Caligula and Tiberius
would have been fraught with suspicion, with paranoia...
Caligula, a young man,
who now has to live with the guy who has ruined his life up to that point.
[narrator] Confined to his room,
Caligula finds himself forced to stay on Capri.
Now, all he can do is wait to see what Tiberius has planned for him.
[Adrian Murdoch] Caligula was a hostage on Capri,
and if the emperor had had any problems, he could've been got rid of.
It's part of the old dictum of "Keep your friends close and your enemies closer."
Tiberius could keep a close eye with him,
and would have no compunction about killing him
at the slightest drop of a hat.
[narrator] With Tiberius isolated on Capri,
the Roman people are left without their leader,
causing irreversible damage to his reputation as an emperor.
Tiberius decided to disappear to the island of Capri
and rule from a distance.
However, his retreat to Capri was not well-received.
And then all the rumors of the strange goings on at the island didn't really do his reputation much credit either.
[crowd clamoring]
[whip cracks]
Tiberius ruled in a way that he thought was what the Empire needed.
But he didn't go out of the way to look after people.
[Adrian Murdoch] It was this common touch
that Tiberius missed at every stage of his career.
And when he retired to Capri,
it was a "screw you" to the Senate.
[narrator] Removed from Rome,
Tiberius needs someone to keep the Empire running.
So he makes one of his most loyal soldiers the new head of the Praetorian Guard.
His name is Macro.
Macro was responsible for the security of the fabric of Rome.
He knew every corner.
He knew all the shortcuts,
he knew all the factions and where everyone was going to be.
When he was promoted to the Praetorian Guard,
this simply added another layer of power to him,
and he was, by the time he'd been promoted, a very, very powerful man.
[narrator] Unsure of his fate,
Caligula has no choice but to wait out his time on the island as a prisoner,
but he's not the only person staying in the emperor's villa.
Tiberius' 12-year-old grandson, Gemellus, also lives in the palace.
Do you know why Caligula is here?
I brought Caligula here because you're not ready.
-But I'm your grandson! -It doesn't matter.
All anyone would see is a spoiled brat sitting on the throne,
-incapable of ruling an empire. -I'm capable.
You think if Caligula comes to power, he will let you live?
You no longer have the luxury of childhood.
[sighs]
[narrator] While Gemellus could continue the family reign,
Tiberius knows that by handing the throne to a child,
he'd be putting the entire Roman Empire in danger.
[Tiberius] The Senate is expecting me to name a new heir.
Your cousin, Gemellus, is the obvious choice.
But he's young.
And even when he comes of age,
he was raised as my grandson.
Spoiled. Soft.
The Senate might prefer the son of Germanicus.
You're naming me next in line?
I'm considering it.
Will you release my mother?
You earn my trust,
and I will.
[suspenseful music playing]
[Amanda Ruggeri] Caligula was incredibly intelligent.
He was very savvy.
So when he's brought to Capri,
the entire time you have to imagine he's trying to figure out,
"How do I survive this?"
[male aide] There's been reports of ongoing unrest along the border of Gaul.
Germanic tribes from east of the Rhine have been crossing into the territory.
[Tiberius] Gemellus,
what would you suggest?
Can't we just send an army and attack them?
Caligula, do you agree?
[Caligula] The last thing we want is a full scale war with Germania.
We could send a legion to patrol the border,
stationing them on the west bank with strict orders not to cross.
Their presence should be enough to deter the tribes from raiding.
See to it a legion is sent to the Rhine.
With strict orders not to cross.
There was a process on the Island of Capri,
I mean, it was a dynamic,
in which Caligula and Gemellus were auditioning for the role of emperor.
It's hard not to feel sorry for Gemellus, Tiberius' grandson.
He should have been the natural successor to Tiberius,
but it's notable also that Gemellus wasn't trained in the same way that Caligula was.
[man] Capri's an interesting place, isn't it?
I don't envy your position.
It's all right.
You really do remind me of him.
Your father.
You knew my father?
I served with him when he was Consul.
He would have made a great emperor, had he gotten the chance.
The throne belonged to your father.
It belongs to you.
It was what Augustus wanted.
Instead, we've been left with a demented old man,
driving the Empire to its ruin.
If the Senate has any say in the matter, it'll be you who inherits the throne.
The sooner, the better.
Our sources are full of deliciously horrible stories
about Tiberius on Capri.
Tiberius supposedly had his enemies tossed from the top of the cliff into the sea.
So Caligula could only have known how uneasy his position was,
how dangerous it was to betray Tiberius' trust.
Come. Sit.
[Tiberius] Would you like to join them?
If you want to be emperor one day,
you must learn what it means to live like an emperor.
Go on.
I insist.
[Anthony Everitt] Caligula was summoned by Tiberius to train him up and to give him a little bit of his wisdom.
Tiberius encouraged Caligula in all kinds of vices around sex.
[Anthony Murdoch] The Romans were much more sexually liberated
than certainly we were, or anyone rediscovering them in the Renaissance.
Also, the Romans tended not to care about sexual mores.
Listen to me very carefully. Are you listening?
Yes.
Do not speak unless spoken to.
Tell the truth.
And do not show any emotion.
-Understand? -Yeah.
I'd never speak out against you!
Ever! I swear!
She's lying!
I'm not.
What did he say to you?
[yells] What did he say?
He said-- He said that you're a demented old man.
And that if it were up to the Senate,
I should be the one to inherit the throne.
The sooner, the better.
Kill him.
[gasps, mutters]
-[slicing noise] -[man groans in pain]
[man screams]
[squishing sound]
The one thing we're told about how Caligula was able to ingratiate himself
to Tiberius was not showing any emotion whatsoever.
Tiberius was known for his dissimulation, for his hiding his emotions.
And Caligula tried to out-Tiberius Tiberius.
Living under the emperor Tiberius, there was every single reason to fear.
[coughing]
[narrator] Six years after bringing Caligula to Capri,
Tiberius has fallen ill.
But he still hasn't named a successor,
and now time is running out.
Tell me, honestly.
He doesn't have much time.
[Tiberius coughing]
[narrator] With the emperor on his deathbed,
Macro knows he has to get Caligula on his side.
[Macro] I'm sorry to interrupt.
Yes? What is it?
Your mother.
She's passed away.
When?
A few years ago.
I've just found out.
[Caligula exhales sharply]
[Amanda Ruggeri] When Caligula finds out what happened to the rest of his family,
his mother, his two brothers, he doesn't react.
He has no emotional reaction.
He had simply learned that to react poorly
was almost certainly to bring some kind of punishment down on him,
whether that was exile, imprisonment, or execution.
[narrator] When Caligula arrived in Capri,
Tiberius' grandson, Gemellus, was a spoiled 12-year-old
who believed he was entitled to the throne.
But now, at 18, Gemellus' bloodline
is the only thing keeping Caligula from becoming the next emperor.
The reality is that Caligula is beloved by the Roman people.
Caligula has the ancestry,
he has the history, and all he really has to do is show up.
And Caligula is immediately going to be better liked, more influential,
and more powerful than Gemellus will be.
By considering Gemellus as his heir,
Tiberius is essentially trying to buy time for his grandson.
Because the reality is is that if he doesn't become princeps,
that Gemellus could be killed because he is a liability.
[narrator] In 37 A.D.,
Tiberius makes his decision.
Tomorrow, in the Senate, there will be a reading of my final will.
So there can be no confusion about my intentions.
I have decided...
the two of you shall rule together, as brothers.
I'm naming you co-heirs to the throne.
[suspenseful music playing]
Tiberius must have known that you can't split an empire in half.
I think he just decided to kind of leave it up to fate
and hope that something would work out.
[narrator] Caligula now has a choice:
respect Tiberius' wishes and share the throne,
or take out the one person standing in his way of becoming emperor.
[music intensifies] [theme music playing]