Unity is the dominant government of the central human colonies. It was established in response to the alien massacre and the need to band humanity together under one banner.
Ever since its inception in the First Year of Unity, Unity has been run by the Council of Unity, headed by the Archon. Originally the Council was made up of the seven CEOs of the coalition corporations, as well as a representative from each geographic faction of the Earth States Commonwealth, a senior member of the Church of Intentionality, and a military advisor.
This was changed in U12 when the Council as it stood was dissolved. In its place the Archon created the Ministries.