Julio-Claudian dynasty reign as being strongly influenced by his mother Agrippina, his tutor Seneca, and the Praetorian Prefect Burrus, especially in the first year. He was made Emperor over his step-brother, Claudius' son Britannicus, who he had killed. Agrippina was believed to have poisoned Claudius, having allegedly poisoned her second husband Gaius Sallustius Crispus Passienus. She had also arranged the deaths of Caligula's third wife, Lollia Paulina and Messalina's mother Domitia Lepida the Younger. She saw that the dynasty's numbers dwindle with the execution of Marcus Junius Silanus Torquatus, a grandson of Julia the Younger, to strengthen Nero's claim, having previously arranged
Agrippina the Elder was made "princeps". While Germanicus was administering the oath of fealty to Tiberius, a mutiny began among the forces on the Rhine. During the mutiny, Agrippina brought out their sixth child, Gaius, and made preparations to take him away to a safer town nearby. He was in a full army outfit including the legionary hobnailed boots ("caligae"). These military-booties earned Gaius the nickname "Caligula" (lit. "little boots"), and garnered sympathy for Agrippina and the child among the soldiery. Tacitus attributes her actions as having quelled the mutiny (Tacitus, "Annals" 1.40–4). Once the mutiny was put to an end, Germanicus allowed