Piso’s machinations, encouraged by the reports which reached him of the emperor’s displeasure at the conduct of Germanicus, caused the gravest friction.  Finally, on the return from Egypt through Syria, Germanicus became desperately ill.  He declared his own belief that Piso and his wife had poisoned him; and, on his death, the rumour met general credence, though it was unsupported by evidence.  Agrippina returned to Rome, bent on vengeance, and the object of universal sympathy.  Piso attempted to make himself master of Syria, but failed to win over the legions, and then resolved to return to Rome and defy his accusers.

About this time Arminius was killed in attempting to make himself king.  Shortly before, Tiberius had rejected with becoming dignity a rival chief’s offer to poison the national hero of German independence.

On the arrival in Italy of Agrippina with the ashes of Germanicus, the popular and official expressions of grief and sympathy were almost unprecedented.  This public display was not at all encouraged by Tiberius himself.  Drusus was instructed to emphasize the fact that Piso must not be held either guilty or innocent, till the case had been sifted.  Tiberius insisted that not he, but the senate, must be the judge; the case must be decided on its merits, not out of consideration for his own outraged feelings.  Piso was charged with having corrupted the soldiery, levied war on the province of Syria, and poisoned Germanicus.  All except the last charge were proved up to the hilt; for that alone there was no evidence.  Piso, however, despaired, fearing less the ebullitions of popular wrath than the emotionless implacability of the emperor.  He was found dead in his room; but whether by his own act or that of Tiberius, was generally doubted.  The penalties imposed on his wife and son were mitigated by the emperor himself.

A number of notorious scandals at this period emphasise the degradation of morals and the disregard for the sanctity of the marriage tie in a society where children were regarded as a burden, in spite of official encouragement of the birth-rate.  There was an instructive debate on a proposal that magistrates appointed to provinces should not take their wives with them.

Risings in Gaul of the Treveri and Aedui created much alarm in Rome; the composure of Tiberius was justified by their decisive suppression.

In Africa, Blaems successfully suppressed, though he did not finally curb, the brigand chief Tacfarinas, who had been building up a nomad empire of his own.  It was under Dolabella, the successor of Blaems, that Tacfarinas was completely overthrown and slain.