was a Roman emperor from 161 to 180 and a Stoic philosopher. He was the last of the rulers known as the Five Good Emperors (a term coined some 13 centuries later by Niccolò Machiavelli), and the last emperor of the Pax Romana (27 BC to 180 AD), an age of relative peace and stability for the Roman Empire. He served as Roman consul in 140, 145, and 161.
