Upon the murder of Caligula by the praetorian guards on January 24, 41 AD, there were only three surviving males in the Julio-Claudian dynasty that had been ruling the Roman Empire – Claudius (50, son of Nero Claudius Drusus and Antonia); Nero (4, son of Gnaeus Domitius Ahenobarbus and Agrippina Junior); and Brittanicus (1, son of Claudius and Valeria Messalina). While Caligula was being relieved of his mortal coil, Claudius hid behind some curtains in the palace. The praetorians found him and led him to their camp. To his great surprise, he was there elevated to emperor for two likely reasons – the Senate was debating possibly turning from the Empire model and back to the old Republican one; and the praetorians likely expected they could easily control Claudius because of his impaired constitution from his childhood diseases and his speech impediment. This is a category of Claudius coins.
Although Claudius was in the background of Roman politics until his ascension, he had a very active and conflicted personal life. He was involved in six arranged marriages, four of them actually coming to fruition. The first two marriages didn’t pan out – his proposed first wife, Aemilia Lepida, was the daughter of parents who later fell out of favor, so the wedding was called off. His second was to be to Livia Medullina, but she died on the day of the wedding. The next was Claudius’s first successful marriage, to Plautia Urgulanilla, which produced a son and daughter. The marriage itself was not a success, as they divorced c. 24 AD on suspicion of Plautia’s adultery and that she was trying to murder Claudius. Their son choked on a pear and died and their daughter was suspected to actually have been from Plautia and Claudius’s freedman Boter, so she was disowned.
Claudius’s fourth marriage was to Aelia Paetina and had a daughter named Claudia Antonia with her. He divorced Paetina in 31 AD and began a relationship with a concubine named Calpurnia. That affair lasted 8 years until in 39 AD, Claudius married Valeria Messalina, who was only 14 at the time. They had a daughter named Claudia Octavia and a son named Germanicus, who was later renamed Brittanicus after Claudius’s victory in Britain in 43 AD.
While Claudius was away in Ostia, Valeria Messalina fell in love with the consul-designate, Gaius Silius, and married him in 48 AD. Claudius found out about the marriage and had Silius brought to the praetorian camp, where he was executed. Messalina committed suicide and a damnatio memoriae was pronounced against her.
Claudius’s final marriage was to his niece, Agrippina Junior, in 50 AD. With this marriage came the adoption of Agrippina’s son, Lucius Domitius Ahenobarbus, who was then renamed Nero Claudius Caesar Augustus Germanicus (or Nero, for short). During the next four years, Agrippina plotted her takeover, slowly and methodically replacing everyone in the palace loyal to Claudius with those loyal to her instead. In 54, Nero was approaching his 17th birthday and although Agrippina had already been hailed Augusta, she would soon lose her regency over the throne if Nero weren’t elevated soon. As such she needed to make her move quickly. At dinner on October 12, she fed Claudius a plate of poisoned mushrooms, but they didn’t work. She convinced Claudius’s doctor to give him a second plate, which were successful during the night. With Claudius out of the way, Nero became emperor. Four months later, Brittanicus was poisoned at another dinner party, removing the only legitimate rival to the throne.