Agrippina the Elder has lived for the past decade on the Palatine Hill in Rome, raising her remaining children between her, Livia Drusilla and Germanicus’ mother Antonia Minor.
Agrippina has become lonely, distressed, physically ill and many of her relatives have died.
Agrippina has a hasty, uncomfortable relationship with Tiberius and possibly with Tiberius’ mother Livia.
She has become involved in politics in Tiberius’ imperial court, become an advocate for her sons to succeed Tiberius, and opposes Tiberius’ natural son and natural grandson Tiberius Gemellus for succession.
She is unwise in her complaints about Germanicus’ death to Tiberius.
Tiberius took Agrippina by her hand and quoted the Greek line: “And if you are not queen, my dear, have I then you wrong?”
Agrippina has become involved in a group of Roman Senators who oppose the growing power and influence of the notorious Sejanus, the Praetorian Prefect left in charge of Rome by the voluntary withdrawal of Tiberius to the Isle of Capri.
Tiberius had begun to distrust Agrippina by 26, when Agrippina requested Tiberius to allow her to marry her brother-in-law, Roman Senator Gaius Asinius Gallus Saloninus.
However, Tiberius didn’t allow her to marry Saloninus, because of political implications the marriage could have.
Tiberius at one point invited Agrippina to a carefully staged dinner at the imperial palace, at which the emperor had offered her an apple as a test of Agrippina’s feelings towards him.
Suspected that the apple could be poisoned, she refused to taste it.
This was the last time that Tiberius invited Agrippina to his dinner table; she later stated that Tiberius tried to poison her.
The position of Sejanus is not quite that of successor; he had requested marriage in CE 25 to Tiberius's niece, Livilla, and under pressure had quickly withdrawn the request.
While Sejanus's Praetorians control the imperial post, and therefore the information that Tiberius receives from Rome and the information Rome receives from Tiberius, the presence of Livia seems to have checked his overt power for a time.
Her death in CE 29 changes all that.
Sejanus begins a series of purge trials of Senators and wealthy equestrians in the city of Rome, removing those capable of opposing his power as well as extending the imperial (and his own) treasury.
Tiberius falsely accuses Agrippina of planning to take sanctuary beside the image of Augustus or with the Roman Army abroad.
Agrippina and her sons Nero and Drusus are arrested on the orders of Tiberius and put on trial by the Roman Senate.
She is banished on Tiberius’ orders to the island of Pandataria (now called Ventotene) in the Tyrrhenian Sea off the coast of Campania, the very island where her mother had been banished.