ZID is the eighth of the thirty Aethyrs, or Airs, of the Enochian system, the thirty spiritual regions delivered to the mathematician John Dee and the scryer Edward Kelley in 1584, and named in the record Dee compiled from those sessions. Its three-letter name, ZID, was received letter by letter through Kelley's scrying.
Place in the system
Each Aethyr is said to contain three Governors among whom the ninety-one Parts of the Earth are divided.
The thirty Aethyrs are the raw gift of the Dee-Kelley sessions; the elaborate visionary content attached to them in modern practice belongs to a later layer, above all Aleister Crowley's The Vision and the Voice, his record of scrying all thirty Aethyrs in 1900 and 1909. The Aethyr is described here as an element of that documented historical tradition, studied as such, its entities not reified.
The three Governors
ZID's three Parts are Zamfres, ruling Mantiana, most plausibly the Matiane of the classical geographers around Lake Urmia, under King Gebabal of the tribe of Asher; Todnaon, ruling a Part called Soxia that answers to no known place, under King Olpaged of the tribe of Dan; and Pristac, ruling Gallia, under King Zarzilg of the tribe of Naphtali. The angel Nalvage, introducing this portion of the work to Dee, said that the remaining thirty Calls belonged to ninety-one Princes and Spiritual Governors to whom the earth had been delivered as a portion, the closest thing the record gives to a stated definition of the whole scheme.