Imperium

• The basis for Roman Government was the concept of Imperium, which was conferred by the Roman Law, ‘Lex Curiata de Imperio’, and gave the legal Right to Command, both military and civil. Unauthorised exercise of Imperium was a capital offence.
• Imperium was implemented by an Imperator, a commander such as the Consul, Proconsul, Prefect, Promagistrate or the Emperor.

Description

• Imperium was the Power vested by the State, through the Roman Senate, as opposed to ‘Regnum’ which was inherited.
• Imperium was conferred by the Roman Law, ‘Lex Curiata de Imperio’, which gave the legal Right to Command.
• Unauthorised exercise of Imperium was a Capital Offence punishable by death, which is why when Sulla crossed the Pomerium in 88 BCE, none of his Generals followed him.
• Imperium was suspended upon entering the Pomerium.

The Three Categories of Imperium

1. Imperium Proconsulare Maius
   • The Roman Emperors were given ‘Imperium’ through a Law called ‘Imperium Proconsulare Maius’, allowing them to override the Consulur ‘Imperium’ of Provincial Governors and Generals.
2. Proconsular Imperium
3. Praetorian Imperium or Propraetorian Imperium (Legatus Propraetore)