What effect did Marcus Aurelius's actions have on the strength and skill of the Roman army? Officers in the army now achieved promotion based on their social status.
Officers in the army now organized into more permanent social rankings.
Officers in the army now achieved promotion due to their ability and merit.
Officers in the army now controlled larger legions and had more authority.

Marcus Aurelius changed the military and this change was one of the notable features of his reign. He promoted the army officers and civilians administrators on merit rather than on noble birth. He appointed capable people to posts most suited to their abilities. This way he laid the foundations of social mobility and broadened the recruitment base for armies, allowing for greater future flexibility.

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During the old kingdom (c 2686-c 2160 bce)