Pax Romana

The Pax Romana (Latin for 'Roman Peace'; IPA: [paːks rɔːˈmaːna]) is a roughly 200-year-long period of ancient Rome that is identified as a golden age of increased and sustained Roman imperialism, prosperous stability, hegemonic power, regional expansion, and relative peace and order, although it still featured a number of internal revolts and external wars, including the Roman–Persian wars. Traditionally, the onset is understood to be the ascent of Augustus, who also founded the Roman principate, in 27 BC. Conversely, the end of the era is considered as 180 AD with the death of Marcus Aurelius, the last of the "Five Good Emperors".

It was during this period that the Roman Empire achieved its greatest territorial extent under Trajan in 117. Additionally, the Roman Empire's population is estimated to have peaked at 70 million people during the Pax Romana, accounting for 33% of the world's population. Following the Pax Romana, and according to Cassius Dio, the dictatorial reign of Commodus, later followed by the Year of the Five Emperors and the Crisis of the Third Century, marked Rome's descent "from a kingdom of gold to one of iron and rust".