La politica dinastica di Caligola e la cosiddetta congiura del 39 d.C.

According to modern scholars, Caligula’s dynastic policy underwent a sudden change as a result of a conspiracy planned (but not carried out) against him by his former brother-in-law and heres designatus, Marcus Aemilius Lepidus, and his sisters Agrippina and Livilla and involving the legatus of Upper Germany, Cn. Cornelius Lentulus Gaetulicus, too. Despite the difficulty to reconstruct the real background and the true aims of this conspiracy, as well as to identify all the involved persons and the role played by each one of them, no one has ever seriously questioned the authenticity of this alleged plot, even if, as a matter of fact, it was not carried out. Indeed, the news about this planned conspiracy, which have been trasmitted both by Suetonius and Dio Cassius, are based on the same common primary source, a letter addressed to the senate by Caligula himself to explain why he had decided to order the exceution of Lepidus and to the relegation of his sisters in an island. If only the attendibility of Caligula’s accuses referred to the plot is questioned, it becomes possible to look at the affair as a whole from an opposite point of view: thus Lepidus, Agrippina and Livilla pass from plotters to victims of a plot by Caligula (most probably under the pressure of his fourth wife, Milonia Cesonia) in order not only to strengthen the dynastic position of his newly born daughter Drusilla and of her mother, but also to get rid of some of the closest emperor’s relatives, whose unmet power ambitions could represent a serious danger for the personal safety of both.