Sanctum Citizens

The citizens of Sanctum are the descendants of Mission Team Alpha and the embryos brought from Earth.

History
The group traces their history to Mission Team Alpha who came to the moon, referred to as Alpha, from Earth aboard Eligius III. At some point, the team split. The people of the Sanctum settlement only consider members of four families to be their founders, excluding other Mission Team Alpha members like Gabriel Santiago. The twelve members of those four families become known as the Primes.

The current Sanctum citizens are descendants of the four families and/or the embryos brought from Earth.

Society
The Sanctum state is led by the Primes. Outwardly, the people are happy and peaceful. The people seem loyal to the Primes and are happy to show their love for "the glory and grace of the Primes". However, there are strict rules and the Primes must always be obeyed. Among the population, there are those who disagree with the Prime's reign.

The society stands on four pillars of Sanctum: Repent, Renew, Rejoice, and Rebirth.

Primes and Hosts
The current Primes are the reborn incarnations of the original twelve Primes. They use Mind Drives to take over bodies of willing hosts. Only those with black blood, also called Royal Blood, are compatible with the Mind Drive. This makes those born with black blood very important and they are called "Hosts". On their Naming Day, the Host's mind is wiped before a Mind Drive is inserted. At that point, the Prime takes over the Host's body and is 'reborn'. Both Primes and Hosts are heavily protected by guards.

Nulls and Oblation
Since black blood is a recessive trait, both parents must carry the gene for a child to be born with Royal Blood. People who do not carry the gene are referred to as "Nulls".

Because Nulls can not bare Hosts (a child with black blood), they are discriminated against in Sanctum. Josephine Lightbourne calls Nulls "less than useless" because they "dilute the bloodline". No child of theirs can have black blood regardless of other parent's genetics (while if two carriers have a child, it's possible for child to be born with black blood), thus they are forbidden from having children.

Their job options are very limited. According to Gabriel Santiago, they can only "clean toilets or volunteer to die as a guard or attend to the dead." Isaac confirms that they can be only janitors or guards.

Josephine wanted to get rid of Nulls to prevent them from further "muddying" the bloodline. Thus she created Oblation: offering Null infants to be killed by the trees. This is one of the reasons why the Children of Gabriel wanted to get rid of Primes.

Carriers
People who carry the Royal Blood gene but do not have black blood themselves are the middle class. They are allowed to have children and have more options for jobs (e.g. Blythe Ann Workman owns a tavern). They are still below Primes but they are above Nulls.

Harvest Festival
A Harvest Festival is where people begin to harvest the fields to collect crops. People are seen dancing during this festival. It most likely happens after a Red Sun.

Naming Day
On Naming Day, the host has an implant containing the mind of one of the original Primes inserted into their neck. The process is similar to what the Grounders do with the Flame. The Flame has the minds of all its previous hosts, but the new host keeps control of their mind and body. Sanctum's Mind Drive's are different – the host is "erased" according to Russell Lightbourne and the chip only contains the mind of the original Prime, not any of the intermediate hosts.

In "The Face Behind the Glass", Delilah is implanted with a Mind Drive, containing a Prime and becomes Priya VII. The same is done with Clarke, and she becomes Josephine. Of the hosts, only Clarke survives due to having A.L.I.E.'s neural mesh inside of her head. The rest of the hosts are mind wiped with nothing of them surviving as shown by an experiment Russell and Gabriel Santiago once did using Red Sun toxin.

The Naming Day begins with a First Confession speech, before people begin making amends. The citizens release lanterns with their wrong doings written on them. A dance is also held, during Naming Day.

Notes and Trivia

 * The citizens perform daily tai chi to show their respect to the glory and grace of the Primes.
 * The practice of giving null infants to the Offering Grove (Oblation) is simliar to how Grounders were noted to kill their young with birth deformites so that their bloodline would remain 'pure'