Jerusalem: The Biography

* Claudius was unlucky in his marriages: he killed one wife and the other killed him. He executed his unfaithful teenaged wife Messalina for treason then married his niece, Julia Agrippina, the sister of Caligula, who started to promote Nero, her son by an earlier marriage, as heir. Claudius made Nero joint heir with his own son Britannicus, named to celebrate his conquest of Britain. On his accession, Nero murdered Britannicus.