Marcus Aurelius

Marcus Aurelius Antoninus (/ɔːˈriːliəs/ aw-REE-lee-əs; 26 April 121 – 17 March 180) was 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 AD 180), an age of relative peace and stability for the Roman Empire. He served as Roman consul in 140, 145, and 161.

Marcus was born during the reign of Hadrian to the emperor's nephew, the praetor Marcus Annius Verus, and the heiress Domitia Calvilla. His father died when he was three, and his mother and grandfather raised him. After Hadrian's adoptive son, Aelius Caesar, died in 138, the emperor adopted Marcus's uncle Antoninus Pius as his new heir. In turn, Antoninus adopted Marcus and Lucius, the son of Aelius. Hadrian died that year, and Antoninus became emperor. Now heir to the throne, Marcus studied Greek and Latin under tutors such as Herodes Atticus and Marcus Cornelius Fronto. He married Antoninus's daughter Faustina in 145.

A bust of young Marcus Aurelius

After Antoninus died in 161, Marcus acceded to the throne alongside his adoptive brother, who reigned under the name Lucius Verus. Under Marcus's rule, the Roman Empire witnessed heavy military conflict. In the East, the Romans fought successfully with a revitalized Parthian Empire and the rebel Kingdom of Armenia. Marcus defeated the Marcomanni, Quadi, and Sarmatian Iazyges in the Marcomannic Wars; however, these and other Germanic peoples began to represent a troubling reality for the Empire. He modified the silver purity of the Roman currency, the denarius. The persecution of Christians in the Roman Empire appears to have increased during Marcus's reign, but his involvement in this is unknown. The Antonine Plague broke out in 165 or 166 and devastated the population of the Roman Empire, causing the deaths of five to ten million people. Lucius Verus may have died from the plague in 169.

Unlike some of his predecessors, Marcus chose not to adopt an heir. His children included Lucilla, who married Lucius, and Commodus, whose succession after Marcus has been a subject of debate among both contemporary and modern historians. The Column and Equestrian Statue of Marcus Aurelius still stand in Rome, where they were erected in celebration of his military victories. Meditations, the writings of "the philosopher" – as contemporary biographers called Marcus – are a significant source of the modern understanding of ancient Stoic philosophy. They have been praised by fellow writers, philosophers, monarchs, and politicians centuries after his death.

The major sources depicting the life and rule of Marcus are patchy and frequently unreliable. The most important group of sources, the biographies contained in the Historia Augusta, claimed to be written by a group of authors at the turn of the 4th century AD, but it is believed they were in fact written by a single author (referred to here as 'the biographer') from about AD 395. The later biographies and the biographies of subordinate emperors and usurpers are unreliable, but the earlier biographies, derived primarily from now-lost earlier sources (Marius Maximus or Ignotus), are much more accurate. For Marcus's life and rule, the biographies of Hadrian, Antoninus, Marcus, and Lucius are largely reliable, but those of Aelius Verus and Avidius Cassius are not.

A body of correspondence between Marcus's tutor Fronto and various Antonine officials survives in a series of patchy manuscripts, covering the period from c. 138 to 166. Marcus's own Meditations offer a window on his inner life, but are largely undateable and make few specific references to worldly affairs. The main narrative source for the period is Cassius Dio, a Greek senator from Bithynian Nicaea who wrote a history of Rome from its founding to 229 in eighty books. Dio is vital for the military history of the period, but his senatorial prejudices and strong opposition to imperial expansion obscure his perspective. Some other literary sources provide specific details: the writings of the physician Galen on the habits of the Antonine elite, the orations of Aelius Aristides on the temper of the times, and the constitutions preserved in the Digest and Codex Justinianeus on Marcus's legal work. Inscriptions and coin finds supplement the literary sources