Titus Avidius Quietus (died by 107) was a Roman politician who flourished under the emperors Domitian, Nerva and Trajan. The offices he held included suffect consul in AD 93 and governor of Roman Britain around 98.
The Younger Pliny mentions that Quietus was an intimate friend of the Stoic philosopher Publius Clodius Thrasea Paetus, a fact Anthony Birley uses to deduce Quietus was born in the early AD 40s. Literary references to other members of his family, the Avidii, indicates they had their origins in Faventia (modern Faenza, Italy), located on the Via Aemilia. Archeological evidence points to Quietus owning at least two houses at Rome, and inscriptions found in Sardinia indicate he owned estates on that island.
Only two posts from his career before he was appointed to the consulship are known. In 82 the veterans of Legio VIII Augusta stationed in Germania Inferior asked Quietus, who is described as leg. Aug. ornatissimo viro, to become the patron of the colony of Deultum in Thrace, where they had settled. This petition, recorded in an inscription set up in Rome, led Birley to suspect that Quietus "was chosen as patron of Deutlum because he was legionary legate at the time the men were settled, i.e. in 82." Later, perhaps in 91-2, Quietus served as Proconsul of Achaea; Birley suggests it was while in this post that Quietus became the friend of Plutarch, who mentions him fondly in his Quaest. conv. and De fraterno amore.
Birley notes that "at first sight it is a little surprising" that Quietus, with clear connections to the Stoics, was appointed to a consulship under Domitian, especially in 93, "the very year when Domitian carried out a major purge of the Stoics." Birley explains that Domitian may have hoped to reconcile with the group until the last moment. Following Domitian's assassination in 97, Quietus spoke in defense of Pliny the Younger before the Senate when the latter attempted to obtain revenge for the Stoic leader Helvidius Priscus. Soon after this speech, he was appointed governor of Roman Britain. Despite Quietus lacking recent military experience, Birley believes his appointment fits the pattern of Nerva's rule, who appointed a number of elder statesmen to positions of power.