Civitas Imperialis is an Imperial term most simply translated as "the Imperial rule of law," although its true meaning is more specific. When the Imperium of Man was founded, the Civitas was laid down to "guarantee the safety and assurance of any citizen of the Imperium of Mankind, wherever he or she travels or sets foot within the length and breadth of the Imperium."[1c] The Civitas was thus an implicit promise to the Imperium's citizens of justice and the protection of the Imperium's soldiers and resources.
The Civitas Imperialis was officially suspended in the Sabbat Worlds in 741.M41, a final acknowledgment that the sector had been lost to the forces of Chaos.[1a] Part of Lord Militant Slaydo's remit from the High Lords of Terra, as the newly-appointed Warmaster of the Sabbat Worlds Crusade, was to restore the Civitas Imperialis to that region.[1b] From his diaries, historians have concluded that Slaydo was determined to do so, within the fullest meaning of the term.[1c]