Marcus Aurelius (Latin: Marcus Aurelius Antoninus Augustus; 26 April 121 – 17 March 180 CE), is Roman Emperor from 161 to 180 AD.

He rules with Lucius Verus as co-emperor from 161 until Verus' death in 169.

He is the last of the "Five Good Emperors", and is also considered one of the most important Stoic philosophers.

During his reign, the Empire defeats a revitalized Parthian Empire; Aurelius' general Avidius Cassius sacks the capital Ctesiphon in 164.

Aurelius fights the Marcomanni, Quadi, and Sarmatians with success during the Marcomannic Wars, but the threat of the Germanic tribes begins to represent a troubling reality for the Empire.

A revolt in the East led by Avidius Cassius fails to gain momentum and is suppressed immediately.

Marcus Aurelius' Stoic tome Meditations, written in Greek while on campaign between 170 and 180, is still revered as a literary monument to a philosophy of service and duty, describing how to find and preserve equanimity in the midst of conflict by following nature as a source of guidance and inspiration.