Final answer:
Emperor Claudius caused a scandal by marrying his niece Agrippina the Younger, which led to political upheaval and suspicions of her involvement in his death. Agrippina's actions overshadowed the previous scandalous behavior of Claudius's wife Messalina, whose supposed promiscuity was emblematic of decay in the imperial household.
Step-by-step explanation:
The Emperor Claudius sent shockwaves through the empire when he married his niece, Agrippina the Younger. This act was considered scandalous not only because of their close familial relation, as Agrippina was Claudius's brother's daughter, but also due to the further political complications it introduced into the Roman imperial family. Agrippina convinced Claudius to adopt her son, Nero, from a previous marriage, which paved the way for Nero's future as emperor and led to suspicions about Agrippina's involvement in Claudius's death in 54 CE.
The concerns about Messalina, Claudius's previous wife, reflect anxieties about the integrity and authority of the emperor's household. Messalina's reputed indiscretions, such as her supposed prostitution described vividly by Juvenal in his Satire 6, contributed to the Roman society's perception of the imperial family's moral decay. After being charged with adultery, Messalina was executed in 48 CE, and her reputation was posthumously tarnished by historical accounts of her alleged sexual escapades.