Chapter
The Chapterhouses — often simply called Chapters — of Gallifrey were the political affiliations of the various Great Houses and Families. There were six chapters, (PROSE: The Ancestor Cell) each representing one of the founders of Time Lord society. Each Chapter had its own dominant colour, and wore robes of that colour during ceremonial occasions, such as the inauguration of a new Lord President. The most prominent was the Prydonian Chapter. The Doctor belonged to this chapter. Additionally, more Lord Presidents came from this one chapter than any other. (TV: The Deadly Assassin)
Its significance was closely followed by the Arcalian and the Patrex Chapters. The remaining three, the Dromeian Chapter, the Cerulean Chapter and the Scendeles Chapter were overshadowed by the first.[source needed]
The heads of the Chapters were the Lord Cardinals, and the chief of these in a chapter was known as the Cardinal Prime (PROSE: Lungbarrow) Both Lenadi (PROSE: Lungbarrow) and Borusa (TV: The Deadly Assassin) served as Cardinal Prime of the Prydonian Chapter.
According to Commander Hallan, marriage was a way of strengthening the bonds between Houses and Chapters. (AUDIO: Spirit)
Interestingly, the roles filled by the six founding Chapters seemed to have been replaced by six Great Houses in the timeline of the War in Heaven; Houses Dvora, Tracolix, Lineacrux, Arprexia, Xianthellipse, and Mirraflex (presumably due to political upheavals and social reforms) (PROSE: The Book of the War)
Chapters
Founders
According to legend there were six founders of the Chapters and modern Gallifreyan life: (PROSE: The Infinity Doctors, PROSE: The Ancestor Cell)
Ceremonial colours
Prydonians used scarlet and orange. Arcalians used green. Patrexes used heliotrope. (TV: The Deadly Assassin) Dromeians used silver-grey and Ceruleans, as the name would indicate, used blue. (PROSE: Lungbarrow) The Scendeles ceremonial robes change from a light pink to a darker shade of red. (PROSE: The Ancestor Cell) The colour gold was reserved for the Gold Usher (TV: The Deadly Assassin)