Early modern period
In the early modern period, the Holy Roman Empire was a union of territories in Central Europe under a Holy Roman Emperor the first of which was Otto I. The last was Francis II, who abdicated and dissolved the Empire in 1806 during the Napoleonic Wars. Despite its name, for much of its history the Empire did not include Rome within its borders.
Pax Romana
The Pax Romana (Latin for "Roman Peace") was a long period of relative peace and stability experienced by the Roman Empire. It is traditionally dated as commencing from the accession of Caesar Augustus, founder of the Roman principate, in 27 BCE and concluding in 180 CE with the death of Marcus Aurelius, the last of the "good emperors". Since it was inaugurated by Augustus with the end of the Final War of the Roman Republic, it is sometimes called the Pax Augusta. During this period of approximately 206 years, the Roman empire achieved its greatest territorial extent and its population reached a maximum of up to 70 million people – a third of the world’s population. 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 the descent "from a kingdom of gold to one of iron and rust".