Agrippina in Harpers Dictionary of Classical Antiquities

Daughter of Germanicus and Agrippina (supra), and mother of the emperor Nero, was born at Oppidum Ubiorum, afterwards called, in honour of her, Colonia Agrippina, now Cologne. She was beautiful and intelligent, but licentious, cruel, and ambitious. She was first married to Cn. Domitius Ahenobarbus (A.D. 28), by whom she had a son, afterwards the emperor Nero; next to Crispus Passienus; and thirdly to the emperor Claudius (A.D. 49), although she was his niece. In A.D. 50 she prevailed upon Claudius to adopt her son, to the prejudice of his own son Britannicus; and, in order to secure the succession for Nero, she poisoned the emperor in A.D. 54. The young emperor soon became tired of the ascendency of his mother, and, after making several attempts to shake off her authority, he caused her to be assassinated in A.D. 59.