Imperiatrix was a title held by the leader of the Time Lords during times when the High Council was disbanded, and the leader ruled in a more dictatorial manner. Imperiatrix personal guards were known as the Imperial Guard. Pandora, the first female ruler after Rassilon, took the title Imperiatrix as she exercised more power than her position allowed. The High Council deposed her and had her dispersed from history. (AUDIO: Imperiatrix, Lies) Madam President Romana temporarily took the title to prevent a newly resurrected Pandora from usurping Romana's rule. (AUDIO: Imperiatrix)