Upon the death of his uncle Emperor Antonius Pius (who had adopted him), at the age of 40 Marcus Aurelius, along with his incompetent brother Lucius, ascended to the throne. They shared power until Lucius' death in 169 AD after which Marcus ruled alone until his own death.
As an emperor, Aurelius was conservative and just by Roman standards. The sole objective of his government was the happiness of its people. Unfortunately, his rule was beset by internal disturbances of famine, plague, earthquakes and fires, and by external fighting with the Germans along the Danube, barbarians from the north, and the Parthians in the east.
Year after year Aurelius fought hard to push the barbarians back, but as time went on he lived to see the crumbling of Roman borders. During his reign the celebrated Pax Romana collapsed perhaps making him turn more and more to the study of Stoic philosophy.
It was in the midst of this strife and towards the end of his life that Marcus Aurelius wrote what has amazingly come down to us as the Meditations, or his writings to himself (Ta eis heauton).
Unlike the typical philosophical treatise with a sustained argument for an eloquent position, the Meditations are a journal of disconnected musings, aphorisms and person remonstration.
Marcus Aurelius' views were based on the version of Stoicism developed by the freed slave Epictetus whose two basic principles were - endure and abstain.
Also, like Seneca , he believed that a divine providence had placed reason in man and it was in man's power to be one with the rational purpose of the universe.
His Meditations also expressed the Stoic pantheistic view that All is One; that God is the universe and the universe is God and that the goal of human existence is to live consistently with nature, which means "consistently with reason".
Along with other later Stoics who were more concerned with ethics than metaphysics, Marcus Aurelius dealt primarily with how one ought to live.
Echoing Epictetus, he states that one must make the distinction between what is up to us and what is not up to us. We only have control over our opinions and attitudes. Therefore, it is not what happens to us that is important, only our reaction to it. Our opinion of the circumstance, rather than the circumstance itself, is everything.
Although Aurelius was no friend to Christianity, his work Meditations was attractive to Christian scholars. They saw him as a pagan struggling towards a view of life expressed in Christian doctrine. His notion of providence, his modesty and temperance, his being critical of his own imperfect virtue and his advocating the control of one's attitudes and desires were consistent with the Christian point of view.
From the time of his death until the invention of printing, philosophers, Christian theologians and medieval scholars kept his writings alive. Meditations, which consists of twelve books, was first printed in English in 1634.