Custos Militaris Maximus

The Custos Militaris Maximus/a (Latina: Supreme Caretaker/Keeper of the Military [of Rome]) is the Supreme Administrator and peacetime/de facto Commander-in-Chief of the Roman military. They only defer to the Princeps (Augustus) and thus to the senate, serving as the executive of the Praetor Maximus (Minister of Defence) to the emperor. Most Custos Militaris were mages, and more than half of them were women due to this.

Origin and History
After their victory in 30 BC over Antonius, the newly minted Augustus sought a way to keep his friends/allies close while not endangering his own power. While he could placate his troubles concerning Agrippa with marrying him to his daughter Iulia, the enigmatic Caesia Tullia Cicero, who commanded three legions directly and five through association, was not so easily leashed, although she could not, as a woman, take part in active politics (but certainly could have promoted any of the male members of her family if she so chose). Eventually, Cicero herself came up with the solution of putting her in charge of anything concerning warfare of the empire, with Augustus staying the actual emperor, calling herself "custodian". In accordance to Augustus' desires, as well as Caesia's extreme political neutrality, it was decided that whoever held the title of Custos was not allowed to hold any other high office; while this was mostly reflecting the fact that Caesia as a woman couldn't hold any office but certain priesthoods (Venus, Minerva, Juno), it also was to keep potential rivalries at bay and considered the massive responsibilities the Custodian has.

Due to being the only high office besides Legate and Military Praetor a woman could hold (provided she was a mage) outside of priesthood, nearly all Custodians until the lex Flavia de aequitate hominium (Declaration of Equality) in 963 AD were female mages; and even after that it was more likely to be held by woman than a man.

Duties and Authority
While the nominal Supreme Commander of the Roman military are the Consuls in wartime and the Praetor Maximus in peacetime, who defer to the Parliament and the Emperor, the Custodian is the executive leader of the military. Their duties thus are similar to that of the Inspector General of the Bundeswehr of Germany, advising the Emperor and the Ministry of Defence. However, due to historical reasons (Cicerona being Augustus' military leader), the Custodian has far more authority than the Inspector General or other, similar positions in other nations, being the de facto leader of the military. As such, the Custodian is the only person in the Empire to hold imperio, the right to lead an army aside from the actual Commander-in-Chief, and thus the right to hold a Triumph. (Traditionally, the Custos offers the symbol of their victory – the Laurel wreath – to the Emperor, who will hand it back to acknowledge the achievement.)

Known Custodians

 * Caesia Tullia Cicero
 * Viridia Tullia Cicero
 * Aquiliana Tullia Cicero
 * Titus Flavius Vespasianus, Son of Titus Minor
 * Constantine the Christian