Corpora
Search for "2. Principalities" for a list of the minimum requirements for principality status.
Search for "B. ESTABLISHMENT AND ADVANCEMENT OF BRANCHES" for information on the process to change branch status.
Also search for "princ" to locate other information on matters pertaining to principalities and principality coronets.
An Tir Kingdom Law on Principalities, and Crown Principalities
Kingdom Law
Includes Laws of the Principality of the Summits and Laws of the Principality of Avacal
Principality of Avacal website
Principality of Tir Righ website (go to their Library, then Archives for look at the North/Tir Righ Principality process)
Principality of the Summits website