T. E. Lawrence ("Lawrence of Arabia"), Graves states, "I chose Claudius for a number of reasons: the first was that he was a historian before he was anything else," He adds that Claudius's "naive optimism & curiosity kept him going" (Martin Seymour-Smith,Robert Graves, p. 256). Claudius's role as observer and interpreter of history seems to have been crucial in Graves's decision to make

him the protagonist of the novel. Of Claudius, Graves says, "I identify myself with him historically, but merely historically." Claudius is a voice with which Graves feels comfortable.

Although the personality of the historical Claudius is not known, Graves draws inferences about him from what is recorded of his actions. He was an ugly and sickly man whose ascension to emperor in A.D. 41 was a matter of being in the right place at the right time. He was an historian who seems to have understood his nation's history particularly well. The conflict between Claudius's roles as historical observer and maker of history as emperor creates friction throughout I, Claudius and its sequel, Claudius the God (1934). Graves fills out the personality by making him modest and quick-witted. The many important public works, such as aqueducts, undertaken by the historical Claudius imply that he was concerned about the well-being of his people. His efforts to make Roman nobility behave responsibly imply that he was a basically honorable man. On the other hand, he proclaimed silly laws that seem utterly capricious, making him seem to be a buffoon. Out of these spare facts. Graves creates a character as full and alive as any in modern literature. The contradictions of Claudius's life are accounted for in a complex character who wants to discredit the monarchy but whose good heart inspires him to try to ease the suffering brought by the emperors of Rome and to improve the lot of the citizens of Rome.

Livia is virtually evil personified. Her efforts to secure the succession to the throne for Tiberius, who does not want it, result in misery for those around her. Scheming is second nature for her. At first, she uses her beauty to ensnare men, including Augustus Caesar. Later, her proximity to the throne frightens people into doing her will. Others she bribes with money or powerful positions. The events of J, Claudius are portrayed as her legacy. Having murdered all threats to her or Tiberius, and having encouraged deceit and treachery, she leaves at her death an insane and embittered family. The retiring Tiberius sulks and indulges in degenerate debauchery; Caligula is evilly insane, indulging in delusions that he really is a god; and Claudius is so horrified by the mad outrages of the Imperial family that he nostalgically yearns for a Republic that he never knew, and fantasizes about the nobility of his murdered father. Livia plays an important role in the themes of the novel. Through her, the beginnings of Rome's degeneracy are shown. Her actions begin the cause-and-effect development of the novel's plot; each succeeding step toward disintegration may be traced back to one or another of Livia's evil deeds.

Most historians note evidence that the historical Livia was conniving and power hungry. She is said to have satisfied her husband Augustus's sexual desires with twelve-year-old girls who were snatched off the streets of Rome by imperial soldiers. In I, Claudius, she is a caricature, almost inhuman, but her characterization is based on historical tradition.

Agrippa
The most important man in Rome after Augustus, Agrippa is Augustus’s oldest friend. Livia favors Augustus’s stepson, Marcellus, over Agrippa for the purposes of making Agrippa jealous. When a strange sickness overcomes Augustus, he is forced to name an heir. He chooses Marcellus at Livia’s behest, forcing Agrippa to request a relocation out of Rome.

Agrippina
The daughter of Julia and widow of Germanicus, Agrippina becomes the de facto leader of Rome’s anti-Tiberius faction following Germanicus’s death.

Athenodorus
Athenodorus is Claudius’s second tutor. Described by Claudius as “a stately old man with dark gentle eyes,” Claudius credits the tutor with instilling in him self-confidence and a love of history.

Augustus Caesar
Augustus, or “Octavian” as he was known before he became Emperor in 27 B.C., claims to be Caesar’s heir. Claudius portrays him as essentially a just, though generally weak leader, who defers to his wife Livia and is blind to her numerous conspiracies. “Augustus ruled the world, but Livia ruled Augustus,” Claudius tells his readers early on. Every attempt he made at placing one of his direct descendants in line for succession, his second wife Livia succeeded in either killing them off or having them exiled. For most of his marriage to Livia, Augustus was unaware of his wife’s conspiracies. It was not until Germanicus returns from his military excursions and informs Augustus of Livia’s evil-doings does he catch on. But by then it is too late; Livia poisons the figs directly on the tree, and Augustus becomes one of her many victims.

Briseis
Briseis, one of Claudius’s slaves, offers faithful friendship and support to her master, and is most remembered in the narration by a dream she relates to Claudius that foretells the way in which he will assume the position of Emperor.

Caligula
After Tiberius dies in 37 A.D., Caligula, takes over. His first acts as Emperor are to make amends for the unjust reign of Tiberius, and in the first months of his own reign, the Roman public comes to love him. However, after a “brain fever” nearly kills him, Caligula comes to believe he has metamorphosed into a god. Thereafter his reign as Emperor is marked by madness and capricious acts of sadism, sexual depravity, and cruelty. Friends and family members are killed for no reasons, the private fortunes of citizens are plundered, and the women of Rome are considered the emperor’s personal property. Caligula is eventually killed at the hands of Cassius, one of his soldiers, and succeeded by Claudius.

Calpurnia
As Claudius’s longtime mistress, the prostitute Calpurnia provides Claudius with advice and friendship and is the only woman who ever truly loves him. Her true feelings for Claudius are revealed by her visible hurt when Claudius announces his marriage to the beautiful Messalina.

Cassius
First known for surviving the massacre in the German forests, Cassius becomes more famously recognized as the solder who assassinates Caligula.

Castor
Castor is Tiberius and Vispania’s son and the husband of Livilla. He is as cruel as his father. When he was named Protector of the People by Tiberius, a clear sign that he would be heir to the emperor, a conspiracy against him unfolds. He dies of consumptive-like symptoms, thus leaving Sejanus with even greater power.

Claudius
Officially known as Tiberius Claudius Drusus Nero Germanicus, and referred to variously as “Claudius the Idiot,” “Claudius the Stammerer,” and “Clau-Clau-Claudius,” he is the narrator of the story and emperor of Rome during his narration. The son of Drusus and grandson of Livia, Claudius is considered by most Romans to be little more than a harmless, if bumbling, idiot, allowed to remain in the company of the imperial family only because of his birthright. But Claudius, over time, proves to be a keen observer of the political and familial intrigue that Rome had become famous for. While taking no sides in any of the familial struggles, he is able to survive the poisoning of Livia, the tyranny of Tiberius, and the madness of Caligula. His deformities make him a figure of scorn, but they also help to keep him under the radars of the legion of conspirators stalking Rome’s streets. Upon Caligula’s assassination in 41 A.D., Claudius is forced against his will to accept the position of emperor, a title he maintains for 13 years.

Drusilla
Drusilla, one of Caligula’s sisters, is known for having sexual relations with him from a very early age. She is referred to as a “she-beast” by Claudius’s mother.

Drusus
Drusus is Claudius’s father. He is highly respected by his son and wildly popular with Romans for his belief in the liberties of the Republic. As a general in the army on the Rhine he is wounded slightly. In a letter to his brother Tiberius, he exhorts Augustus not to continue his rule, for the sake of Republican values. The letter is accidentally read aloud to Augustus and Livia. Augustus replies immediately, asking Drusus to return to Rome, but by the time Augustus’s letter arrives, Drusus has fallen from a horse and is severely injured. It is revealed later that Livia poisoned him. At his deathbed he whispers to Tiberius, in reference to Livia, “Rome has a severe mother.” His death feeds into Livia’s plan to rule Rome through her son, Tiberius.

Gaius
Gaius is Julia’s oldest son by Marcus Agrippa and a favorite of Augustus. Shortly after being made Governor of Asia Minor, he falls sick and dies, another of Livia’s poison victims.

Gemellus
Gemellus is the young son of Livilla and Castor. Caligula kills him for no apparent reason.

Germanicus
Germanicus is the older brother of Claudius and a hugely popular general in the Roman army. Devoutly faithful to Tiberius, Germanicus borrows money to pay mutinous troops and forges a document indicating that the gift came directly from the emperor. As Tiberius’s military successes grow, he becomes more and more unpopular among the populace. Tiberius sends him and his family to Antioch, where a series of foreboding and mysterious events unfold, culminating in his death. It is eventually revealed that his son Caligula had killed him, but the belief at the time is that Piso and his wife Plancina, had done the deed.

Julia
Julia is Augustus’s daughter by his previous marriage. She is married to Marcellus until he dies, then to Agrippa until he dies, and then to Tiberius. Tiberius never loves her, and after he leaves Rome, she engages in nightly orgies throughout the city and is eventually banished for life by Augustus. It is eventually revealed the Livia has been feeding her an aphrodisiac under false pretences. Julia dies of starvation during Tiberius’s reign.

Livia
Livia, the second wife to Augustus and mother of Tiberius and Drusus, is undoubtedly the most powerful individual in the Roman Empire. Her name, Claudius tells us, relates to the Latin word meaning “malignity,” an apt description of her relationship to Rome. “Augustus ruled the world, but Livia ruled Augustus,” Claudius writes. Livia has fooled her husband into divorcing her so she can marry Augustus, whom she has convinced, falsely, that his wife, Scribonia, is having an adulterous affair. Livia’s marriage to Augustus is never consummated; Augustus is a mere instrument in her boundless ambitions. She even provides Augustus with beautiful women with whom he can satisfy his sexual needs. Just before dying, she admits to Claudius that she poisoned several political opponents, including Claudius’s father and son. Livia’s monomaniacal desire is to bring her son Tiberius into the line of succession to the emperor, and she uses every ounce of cunning to see that desire through.

Livilla
Livilla is Claudius’s sister, Castor’s widow, and Sejanus’s mistress. She helps conspire against Postumous by seducing him and having him arrested for attempted rape.

Lucius
Julia’s second son by Marcus Agrippa and adopted son and heir to Augustus, Lucius is an obstacle in Livia’s plan to control Rome. On a trip to Spain, Lucius mysteriously dies, leaving Tiberius as Augustus’s obvious heir.

Macro
Commander of the Praetorian Guard under Tiberius following Sejanus’s execution, Macro serves briefly under Caligula until he is executed by Caligula.

Marcellus
Octavia’s son and Julia’s husband, and adopted son of Augustus, Marcellus is considered a leading candidate to be Augustus’s heir. After being named Augustus’s heir, thus taking Agrippa out of the picture, he is elected to a city magistracy. However, he quickly dies from the same sickness as Augustus, thus leaving Agrippa as the only possible successor. Like so many others, Marcellus falls victim of Livia’s touches of poison.

Medullina
A beautiful girl of thirteen who befriends Claudius and whom Claudius loves and sets out to marry, Medullina is poisoned on her way to the wedding and dies before the marriage can take place.

Messalina
Claudius’s third wife, Messalina, is given to him by Caligula. She is the first woman Claudius loves since his youth. Although I, Claudius ends before Messalina’s true colors are revealed, she comes to be known as one of the most famous harlots in history.

Aelia Paetina
Claudius’s second wife and Sejanus’s adopted sister, Aelia is used by Sejanus to help him become a member, by marriage, of the imperial family.

Piso
Appointed the Roman governor of Syria and Tiberius’s agent, Piso conspires against Germanicus by spying on him and sending false reports back to the Roman Senate. When Germanicus becomes ill, he suspects Piso of black magic. Following Germanicus’s mysterious death, Piso is accused of the murder and forced to stand trial. Because he holds documents that indict the emperor and his wife, before a the trial can be completed, Livia arranges for his wife Plancina to kill him and make the death appear to be a suicide.

Plancina
Out of fear of losing everything she owns, Plancina, Piso’s wife, with Livia’s help, kills her husband Piso and makes the death appear to be a suicide. She herself is then tried, and acquitted, of Germanicus’s murder.

Postumus
One of Claudius’s best friends and grandson to Augustus, and therefore a possible successor to Augustus, Postumus is daring and adventuresome. At the age of fourteen, he protects Claudius from a beating by Cato, Claudius’s tutor. He loves Livilla, which proves to be his downfall. Livilla seduces Postumus and then cries rape, causing Postumus to be banished from Rome. He was eventually freed secretly by Augustus, who had finally come to learn of Livia’s treachery, but it was too late for him to become Emperor. Livia’s further treachery kept him out of Augustus’s will, and when his whereabouts were eventually discovered, he was tortured and killed by Tiberius.

Sejanus
Born of humble origins, Sejanus becomes Commander of the Praetorian Guard under Tiberius and effectively ruled Rome with an iron fist when Tiberius retired to Capri. His thirst for power became too much, however; his excesses, which cause the indiscriminate arrests and deaths of many officials and everyday citizens, lead to his own hideous execution at the hands of Tiberius.

Sibyl at Cumae
Claudius relates his visit to the Sibyl at Cumae, who foresees his ascension to emperor and further tells him that 1900 years hence, despite his “stammer, cluck and trip,” he “shall speak clear,” a reference to the history he writes.

Tiberius
When Augustus dies in 14 B.C., Tiberius, his adopted son and the natural son of Augustus’s wife Livia, becomes emperor. His lasts for twenty-two years, most of them in self-imposed exile on the island of Capri. Claudius portrays Tiberius as being a cruel and degenerate ruler who comes to power primarily as the result of his mother Livia’s murderous plots. Claudius also tells us of Tiberius’s depravity, hinting at acts of bestiality and other depraved sexual practices. Tiberius is on his deathbed, but not quite dead, when he is suffocated by Caligula’s commander Macro.

Urgulanilla
A huge, six-foot two-inch woman whom Livia forces Claudius to marry, Urgulanilla has little to do with Claudius.