The Appalachian Confederation is a rhizome made of up tribes. Tribes are rhizomes made up of people. Individuals do not join the Confederation, tribes do, in precisely the same way that individuals do not join the United Nations, NATO, or even the Better Business Bureau. The Appalachian Confederation is an alliance of tribes--tribes are made up of people, but people belong to the Confederation only through their tribes.
Membership in the Appalachian Confederation is a sacred bond of trust and alliance. It must not be taken lightly. For this reason, any tribe seeking to join the Appalachian Confederation must be approved by the unanimous consent of all the tribes currently in the Confederation, as a single antagonistic relationship can affect the whole Confederation.
The means by which tribes determine their vote internally is left to them. A tribe may decide to determine its vote by a simple majority. The unanimity rule applies only to the votes from all tribes: every tribe must vote for inclusion, not necessarily every person in every tribe.
To ensure that all of the tribes give such an important decision the thought it deserves, such inclusions can only be made at the annual Mountain Festival.