Marcus Aurelius AntoninusĀ Ā 26 April 121 ā 17 March 180) wasĀ Roman emperorĀ from 161 to 180 and aĀ StoicĀ philosopher. He was a member of theĀ NervaāAntonine dynasty, the last of the rulers later known as theĀ Five Good EmperorsĀ and the last emperor of theĀ Pax Romana, an age of relative peace, calm, and stability for theĀ Roman EmpireĀ lasting from 27 BC to 180 AD.