The conspiracy of Gaius Calpurnius Piso in AD 65 was a major turning point in the reign of the Roman emperor Nero (reign 5468). The plot reflected the growing discontent among the ruling class of the Roman state with Nero's increasingly despotic leadership, and as a result is a significant event on the road toward his eventual suicide and the chaos of the Year of the Four Emperors which followed.

A freedman or freedwoman is a formerly enslaved person who has been released from slavery, usually by legal means. Historically, enslaved people were freed by manumission (granted freedom by their captor-owners), emancipation (granted freedom as part of a larger group), or self-purchase. A fugitive slave is a person who escaped enslavement by fleeing.