[Revised October 20, 2016.  This is largely cut-and-paste from my History 121 class.  It's not as full as the account I give in class.   There are much better and more thorough accounts of this period online and in your text.  This will give you a good general picture, but it is only a place to start.]

The Julio-Claudian Emperors of Rome

Well begun is half done, but only half done.  In order for Augustus’ work to be truly successful, he had to find someone to carry on when he was gone.  He had no surviving sons or grandsons, so the task of finding as successor was a bit tricky—especially so since the system he had created worked best of the emperor was closely tied to Julius Caesar and to Augustus himself: being related to a god was a big help in getting people to accept you in a job that meant you were on the way to godhead yourself.

Augustus’ first choice was his nephew Marcellus.  Marcellus was already related to Augustus, but Augustus wanted the tie to himself to be even closer, so he arranged a marriage between Marcellus and Julia, Augustus’s daughter.  All good—except Marcellus dies before Augustus, and Augustus was back at square one.  

Next, Augustus chooses Agrippa—another fine choice.  Agrippa was a great general and administrator, but he had the disadvantage of not being directly related to Augustus.  Not to worry.  Augustus had a daughter—Julia—who was available, having been recently widowed.  All good—except Agrippa dies before Augustus, and Augustus is back at square one.

Now Augustus chooses his stepson Tiberius: not a bad choice, but, again, a man not as clearly connected to the “divine” family as he might be, and Augustus wants the tied to be closer.  Not to worry.  Augustus has a daughter—Julia—who was available, having been recently widowed.  Tiberius is forced to divorce his own wife so he can marry Julia.  And, this time, the designated successor does eventually take over.

Tiberius (AD 14-37) was a skillful administrator, and, in some ways, a more talented man than Augustus.  Nevertheless, he had a real weakness: a tendency to be suspicious to the point of paranoia.  In most situations, this wouldn’t have been a problem, but putting someone like this in a position of supreme power is a potential disaster.

Tiberius trusted only one man, his praetorian prefect, a man named Sejanus, and this was the one man he should not have trusted.  Sejanus had plans of his own, plans to acquire money and power.

The first was easy enough.  Pretending to be concerned about the emperor’s safety, Sejanus convinced Tiberius to investigate and prosecute crimes of “maiestas,” impugning the majesty of the Roman people.  Maiestas was a vague charge (saying anything critical of the emperor could be regarded as maiestas) but it was a very serious charge. Undermining the emperor meant undermining the fragile unity of Rome, possibly renewed civil war. Essentially, then, maiestas was treason, an offense that merited the most severe punishment: not just death, but the confiscation of one’s entire estate as well. And those who ferreted out such crimes deserved a reward, yes?  Well, what about 10% of the confiscated estate?

Note that such terms would lead to a rash of maiestas cases, and many innocent people are going to end up dead.  Further, Sejanus’ can use the maiestas charge to help him eliminate potential rivals in Rome.  And those he can’t get rid of in this way, he gets rid of in other ways.  He seduces the emperor’s daughter-in-law, and, with her help, poisons Tiberius’ son Drusus, making it look like a natural death.  One step closer to the throne for Sejanus.

Further, each maiestas case fed Tiberius paranoia, giving Sejanus even more leverage over the panic-stricken emperor.  Ultimately, Sejanus persuades Tiberius to leave Rome for Capri, while he himself takes over the day to day operation of the city.  Ultimately, he expected to be named Tiberius’ heir.

And at last the day arrived: a letter from Tiberius to be read to the senate.  But instead of making Sejanus his heir, Tiberius called for the immediate arrest and execution of Sejanus.  Somehow, Tiberius had finally seen through Sejanus’ machinations, finding out all sorts of unsavory things about his praetorian prefect.

And so Sejanus is gone—his daughter and son executed too, poor kids—but Rome is no better off.  Now Tiberius is more paranoid than ever, determined to get them before they get him.  He launches a reign of terror, killing anyone he believes is plotting against him—and then killing off their friends and family members because he thinks they are plotting revenge—and then killing off their friends and family members because he thinks they may be plotting revenge—and then…well, so it goes.

Tiberius dies in AD 37, and the Roman people breathe a sigh of relief: but not for long.  The new emperor, Gaius (Caligula) proves even scarier than Tiberius.

Caligula (AD 37-41) began his reign with the enthusiastic support of the people of Rome.  They turned Tiberius’ funeral into a celebration of the new emperor, calling him star, chicken, baby, and pet (yes, I know that’s strange).  Why so enthusiastic? Well, Caligula’s father, Germanicus, had been much loved by the Roman people, a great general.  They thought Caligula would take after his dad—and that’s clearly what dad had wanted.  When Caligula was a little boy, he had dressed his son in military uniform and taken him into camp again and again.  The soldiers loved the little boy in his uniform, a uniform complete with military style boots.  They called the boy “little boots,” and that’s where we get the “Caligula” nickname.  

Unfortunately, after his father’s death, Caligula’s childhood had been a nightmare. His relatives were killed right and left, victims of Sejanus’ plots or Tiberius’ paranoia.  No one survives a childhood like this unscathed, and Caligula began his reign with a lot of psychological baggage. Now adding to that: the strain of being a god.

It’s just not easy to be a god. For one thing, it’s hard to find an appropriate wife.  You need a goddess, right?  Well, Caligula seeks a goddess wife.  He prays that the goddess of the moon will join him as his wife: but she must have had a prior commitment or something, and Caligula has to look elsewhere.  There is a family in Rome producing gods and goddesses, isn’t there?  Why, yes.  His own!  And where can he find a goddess?  Well, what about his sister Drusilla?  So to the destructive psychological mix we now add incest—and disaster is on its way.  And when his beloved Drusilla dies: well, the last thread connecting Caligula to reality is gone.

He can’t deal with problems rationally.  He finds he’s getting a high butcher bill: maintaining the lions, tigers, and bears for his lavish circus shows is expensive. So he looks for a supply of cheap meet.  He goes to the prison, picks out a bunch of prisoners, has the slaughtered up and turned into Purina lion chow.  Well, it did lower the butcher bill….

He took advantage of his power to exploit both men and women sexually, forcing them to engage in all sorts of perversions. And if one didn’t go along, a horrible death awaited.  He kept his prisoners is cages too small to allow them to stand or lie down.  He had people sawn in half, or subjected to the death of a thousand cuts.  He forced parents to laugh and joke with him while their sons were executed—a cruel man.

He finally made the mistake of insulting the wrong people, members of his praetorian guard.  The guardsmen themselves killed him (and his wife and baby daughter too .)   

And now a new emperor: Caligula’s uncle Claudius (AD 41-54).  Claudius was a well-meaning, scholarly man.  He had studied a lot of history, writing many volumes on Augustus.  He was perhaps the last man to know well the ancient Etruscan language. Unfortunately, he was not the kind of man who can be easily accepted as an emperor and soon-to-be god.  He spoke with a stutter, and walked with a limp: something of a buffoon.  Caligula may have let him live only because he enjoyed making fun of his clownish uncle.

Make matters worse: Claudius’ wives.  Claudius third wife, Messalina, was a beautiful young woman, and Claudius was very much in love with her. But a beautiful young woman is not likely to find an awkward man in his fifties much to her taste.  She cheated on Claudius right and left and very openly.  Claudius, already having a hard time with the “emperor” image, has an even tougher time when not even his wife shows him any respect.

Messalina finally goes too far, celebrating a mock marriage ceremony with one of her many lovers.  But Roman marriage customs were less formal than ours, and this “mock” marriage could easily have been regarded as real.  And, since Messalina was as closely tied to the divine Julius Caesar as Claudius himself, any man who took Claudius’ place in bed was a potential threat for taking over his throne as well.

Claudius couldn’t bring himself to deal with the beautiful Messalina directly, but he finally did give his friends the authorization to do what had to be done.  When adultery involves a queen or an empress it is (quite rightly) regarded as an act of treason, and Messalina and her lover were excecuted.

And now, a new wife for Claudius, Agrippina.  Agrippina was also an attractive young woman, but she had a lot more political in the way of political smarts than did Messalina.  She wrapped Claudius around her little finger, and tried to run the empire through him.  But it was a frustrating task.  Claudius was wishy-washy, and, while Agrippina could persuade him to say he was going to take a certain course of action, someone else might talk him out of it.  Frustrating for Agrippina.  She wanted on the throne someone she could depend on to more consistently carry out her wishes—her son by a previous marriage, Nero. Claudius adopts Nero as his heir, and then Agrippina poisons Claudius.

At first, Nero’s reign (AD 54-68) goes well.  He is only 16, and his mother and his advisors are running things.  Eventually, however, Nero tires of his mother’s interference.  One area of conflict: Nero’s marriage.  Agrippina had insisted that Nero marry a woman named Octavia, one of the last surviving relatives of Augustus.  Nero wanted to divorce Octavia and marry his mistress, Poppaea Sabina.  Agrippina said no: have as many mistresses as you want, but, for political reasons, you have to stay married to Octavia.

Nero was afraid to disobey his mother, and he really wanted her out of the picture.  And—being emperor—he could get her out of the picture.  To be free to do what he wanted, Nero ordered his own mother’s execution (AD 59).  

Free from his mother’s interference, Nero can now do what he wants.  He could simply have divorced Octavia, but, instead, he charges her with adultery (hypocrite and liar), has her executed…and gives her severed had to Poppaea Sabina as a present.

Nero is now free to indulge his other tastes as well.  He fancied himself a great artist, and launched an artistic career.  But what he didn’t do was effectively govern Rome.  His misgovernment provoked serious revolts in Britain and Judaea.  And in Rome, Nero failed to handle the great fire of AD 64.  Instead of doing his best to put the fire out, Nero supposedly took the streets with his lyre: singing about the fall of Troy.

Naturally, a man like this provokes enemies, and (like Tiberius), Nero was determined to get them before they got him.  He executed many senators—including his former tutor the philosopher and playwright Seneca—because he thought they were plotting against him.  He executed his greatest general, Corbulo—and this proved a mistake.  Nero’s other generals (stationed in various parts of the empire) were fearful they might be the next targets, and began leading their troops toward Rome in an effort to overthrow Nero.  Nero panics and decides to kill himself.  His famous last words: what an artist the world is losing!

Nero’s death plunged Rome into a new period of civil war: four emperors in the space of a year, each one using his troops ruthlessly in the quest for power.  Roman troops sack and destroy Roman cities, and even attack the city of Rome itself.

And you know what’s surprising in all this?  Once again, the empire grows.  During this period, Egypt, Palestine, and Britain are added to the empire.  Rome grows!  And the systems set up by August will endure for four centuries more in the west, and for over 1000 years in the east.  Is that amazing, or is that amazing?