Marcus Aurelius (121-180 ce) Born on 26 April 121 ce, Marcus Aurelius Antoninus is considered one of the greatest figures in Stoic philosophy. He was born during the reign of the Roman emperor Hadrian, in an upper-class family, to the praetor Marcus Annius Verus and the heiress Domitia Calvilla. Marcus was later adopted by Antoninus Pius, who ascended the throne after Hadrian's death. In 161, after Antoninus Pius died, Marcus succeeded him along with Lucius Verus, his adopted brother. Marcus Aurelius's reign was marked by heavy military conflict with the Parthian Empire in Iran and the rebellious Kingdom of Armenia. Although he was successful in his military campaign against the Parthians, in the later years, Marcus suffered a number of setbacks. These included the Antonine Plague, which broke out around 165 ce, and the eventual death of his co-emperor Lucius Verus, as well as revolts from the eastern provinces. A student of philosophy since his young days, Marcus sought wisdom in the philosophical teachings of the 1st-century Stoic thinker, Epictetus. In his later years, he recorded private notes and ideas on Stoic philosophy, which eventually came to be known as Meditations. Considered the last emperor of the Pax Romana, Marcus Aurelius passed away in 180 ce.