The First Years of the Dual Principate: Marcus Aurelius and Lucius Verus (Aurelius Bio Part 6)

The accession of Marcus Aurelius in 161 AD marked a radical departure from Roman political tradition through the establishment of the first dual principate. Upon the death of Antoninus Pius, Marcus insisted that the Senate confer equal powers upon his brother by adoption, Lucius Verus. This period was characterized by a transition from the lenient ways of Pius to a reign defined by Stoic duty, judicial reform, and external threats.

While Marcus focused on domestic administration from Rome, the early 160s were dominated by the Parthian War in the East and unrest on the Rhine and Danube. The administration professionalized its military and civil posts, replacing literary appointments with experienced commanders. Marcus’ legal activity demonstrated a "partiality for freedom" while social stratification between the honestiores and humiliores became more formalized.

1. The Accession and Dual Principate

The Unprecedented Shared Power

Marcus Aurelius was the designated successor to Antoninus Pius but refused to accept imperial powers unless they were conferred simultaneously on Lucius Verus. For the first time, two emperors ruled with equal power, though Marcus possessed greater auctoritas due to his seniority and reputation.

• Imperial Titles: Marcus became Marcus Aurelius Antoninus Augustus; Lucius became Lucius Aurelius Verus Augustus.
• Public Image: Coinage of 161 AD proclaimed concordia Augustorum—the harmony of the emperors.

Initial Administrative Acts

• The Donative: A bounty of 20,000 sesterces per Praetorian Guard ensured loyalty to both emperors.
• Deification of Pius: Marcus and Lucius delivered funeral orations for the newly deified Divus Antoninus.
• Dynastic Consolidation: Marcus betrothed his daughter Annia Lucilla to Lucius Verus to reinforce their political bond.

2. Military Crises and the Eastern War

The Parthian Invasion

King Vologases III of Parthia took advantage of the succession crisis, invading Roman territory in 161 AD. Disaster struck at Elegia, where Governor M. Sedatius Severianus and his legion were annihilated. Simultaneous unrest arose in Upper Germany, Raetia, and Britain.

The Deployment of Lucius Verus

In 162 AD, Lucius Verus was dispatched eastward due to his youth and endurance. Marcus staffed the campaign with veterans such as Statius Priscus and M. Pontius Laelianus. En route, Lucius fell ill at Canusium before making a ceremonial journey through Athens and Antioch, drawing criticism for luxury.

Successes in the East

• In 163 AD, Statius Priscus captured the Armenian capital, Artaxata.
• A new city, Kaine Polis ("New City"), was built as the new capital.
• Lucius took the title Armeniacus at the end of 163 AD; Marcus accepted it in 164 AD.

3. Domestic Governance and Judicial Reform

Philosophy and Duty

Marcus viewed imperial power as a duty rather than privilege, continuing to study philosophy under Sextus of Chaeronea even as emperor.

Judicial Rigor

• Court Calendar: Extended to 230 days per year to reduce case backlog.
• Professionalization: Relied on expert jurists such as Volusius Maecianus.
• Protective Legislation: Established the praetor tutelaris for orphan cases, promoted manumission rights, and required birth registration within 30 days.

Crises in Rome

A severe flood of the Tiber in 161 AD caused famine and destruction. Marcus and Lucius personally oversaw relief through the grain supply.

4. Key Personalities and Influences

Marcus Aurelius vs. Lucius Verus

The emperors’ temperaments contrasted sharply: Marcus was austere and civic-minded; Lucius preferred luxury, sport, and the company of Panthea, his famed mistress. Despite Lucius’s indulgence, his generals delivered victories under his nominal supervision.

The Influence of Fronto

The tutor Fronto remained a moral and rhetorical guide, urging Marcus to balance philosophy with eloquence befitting a Caesar. His letters offered historical encouragement during military setbacks.

The Imperial Family

• Birth of Twins (161 AD): Faustina bore T. Aurelius Fulvus Antoninus and Lucius Aurelius Commodus; only Commodus survived.
• Faustina’s Role: Inherited her father Pius’s fortune and remained active in imperial affairs alongside Marcus.

5. Social Stratification and Legal Trends

Social and legal divisions deepened during the dual principate, distinguishing the privileged honestiores from the subjugated humiliores. Penalties became class-dependent, and Marcus suppressed corruption firmly, dismissing officers found guilty of bribery.

Visual Presentation of the Dual Throne