Denarius of Antoninus Pius with Marcus Aurelius as Caesar

Dynastic issues were an essential piece of imperial propaganda and political necessity to ensure the stability of the Empire once the Emperor passed. The role of the Emperor is often described as a monarchy, which it was in practice, but its operation was different from the monarchies we understand today. One did not legally become Emperor via birth but due to a series of powers and offices granted by the Legions and the Senate. A person was “imperator” because they had been acclaimed so by the army (often helped by a donative). At the same time, they possessed the power to govern as Consul (COS), and their person was sacrosanct through the power of the Tribunate (TP P), granted by the Senate. The tribunician power was renewed annually and is useful in noting each Emperor’s “regnal” years.

It was essential for a reigning emperor to ensure that his successor was brought along through the various honors and powers before his time came to rule. If a successor was not clearly indicated, established, and held sufficient Auctoritas, a power vacuum would emerge, frequently leading to a Civil War between rival generals. Antoninus Pius’ reign was long, and thus, he had significant time to prepare Marcus Aurelius. Here, the young Aurelius, shown clean-shaven and boyish, is clearly the junior Caesar, but he has already received his first consulship. Upon his accession this young image would be replaced by the aged philosopher and writer of The Mediations, and the young face of Commodus would appear as the next Caesar, continuing the cycle.