Twelve Originators

The Duodecim (十二宗家), also known as the Twelve Spears (矛十二士), are families that quickly adopted Ars Magus during the Dark War, and contributed significantly. They were deeply involved in the formation of the Novus Orbis Librarium. They were formally named after the end of the Dark War by the Librarium, and each of their family names are tied to one of the twelve months.

Information
The family's primary duties are to provide the Novus Orbis Librarium with talented members and to dedicate themselves to the Imperator. Most heirs of the Duodecim join the Military Academy at a young age, usually out of junior high or high school. They have special privileges and responsibilities, for example they have precedence over other students in special classes and student council, and upon graduation are guaranteed at least First Lieutenant rank. They must perform well and serve as role models, volunteer, and take part in events, and if they behave badly they can be stripped of their Duodecim title.

Each family controls at least one Hierarchical City and each month the family meetings are held in one of those cities, where important issues are discussed. The results of these discussions are reported to the Imperator by the family heads. The Duodecim family heads are the only people allowed to meet the Imperator.

Each family has their own rules, traditions, and have different strengths and Ars Armagus.

Duodecim families
The families in order are:
 * The Mutsuki family (ムツキ家) — known as the most powerful family of the Duodecim. However, their relationship with the Librarium has worsened, since they were left in charge of the ruins of the 5th Hierarchical City of Ibukido and started to mouth off to the NOL who like the Vermillion family, began to question their fascist reign. The head of the family is Kagura Mutsuki, who was responsible of taking care of the real successor of the Imperator, Homura Amanohokosaka. The Kohaku family serves the Mutsuki family – they are trained silent assassins.
 * The Kisaragi family (キサラギ家) — they don't care about bloodline or status at all. They gather talented children from all over the world, give them combat training and an education. As a result, the family has a number of extremely influential leaders and soldiers. The family had been nobles in Magister's City: Ishana prior to being members of the Duodecim. It is unknown who is head of their family currently – the last known one was Seven of the Ten Sages. Amongst the Duodecim, the Kisaragi family stands out as extremists that are thought to be borderline mercenaries. Even so, the Kisaragi and Yayoi families get along well with each other, mostly because of their apathetic attitude towards the common folk.
 * The Yayoi family (ヤヨイ家) — the polar opposite of the Kisaragi family, placing utmost importance on their bloodline. As a result, they are close-knit, stable, and strong. However, their strict rules regarding parentage is causing the family to get smaller with each generation, and some believe the family will fall as a result. The NOL has warned them to change their policies, but Tsubaki's father, the head of the family, will not listen. They keep an Ars Armagus, Sealed Armament: Izayoi, under a special lock that can only be opened from the blood of a person from their family. Amongst the Duodecim, the Yayoi family stands out as extremists that are thought to be bloodline-obsessed traditionalists. Even so, the Yayoi and Kisaragi families get along well with each other, mostly because of their apathetic attitude towards the common folk.
 * The Uzuki family (ウヅキ家)
 * The Satsuki family (サツキ家)
 * The Minazuki family (ミナヅキ家)
 * The Fuzuki family (フヅキ家)
 * The Hazuki family (ハヅキ家) — just like Mutsuki family has their servants, Kirihito family. Kirihitos are trained killers, who use variety of toxins and emliminate their targets silently. The head of the family is father of Mai Hazuki.
 * The Nagatsuki family (ナガツキ家)
 * The Kannazuki family (カンナヅキ家)
 * The Shimotsuki family (シモツキ家)
 * The Gokuzuki family (ゴクヅキ家)

Trivia

 * Every family is named after one of the traditional names of the twelve Japanese months.
 * Duodecim [duˈo.de.kim] is a Latin word that means "twelve". Duo translates to two (2) and decem translates to ten (10) in Latin. Combined, they equal 12. Latin numbers after 10 are written backwards, which explains why duo is first.