Agrippina the Younger outraged by Claudius' adoption of Nero and his choice of Nero as successor, instead of choosing his own son Britannicus. Nero and Octavia were married on June 9, 53. Claudius later repented of marrying Agrippina and adopting Nero, began to favor Britannicus, and started preparing him for the throne. His actions allegedly gave Agrippina a motive to eliminate Claudius. The ancient sources say she poisoned Claudius on October 13, 54 with a plate of deadly mushrooms at a banquet, thus enabling Nero to quickly take the throne as emperor. Accounts vary wildly with regard to this private incident and according
Agrippina the Younger first marriage to praetor Tiberius Nero, and was the Emperor Tiberius's younger brother and Augustus's stepson. In the year 9, Augustus ordered and forced Tiberius to adopt Germanicus, who happened to be Tiberius's nephew, as his son and heir. Germanicus was a favorite of his great-uncle Augustus, who hoped that Germanicus would succeed his uncle Tiberius, who was Augustus's own adopted son and heir. This in turn meant that Tiberius was also Agrippina's adoptive grandfather in addition to her paternal great-uncle. Agrippina was born on 6 November in AD 15, or possibly 14, at Oppidum Ubiorum, a Roman outpost on