In Guardians of the Forests, Fengheld covenant is mentioned having a chapter house in a different Tribunal.
For chapter houses that are in different tribunals, how do you handle this in your saga (or how would you)? A chapter house is not an independent covenant, or even a heavily supported one. It's a second physical location used by the magi of the original covenant - all the 'members' of a chapter house are sworn members of the parent covenant, and there's not even any guarantee that the same magi will always live in the chapter house from year to year.
Which tribunal do the Magi belong to? What rights as a covenant (or anything else) does the chapter house have in the Tribunal it sits in?
If you follow the old supplements (IIRC 2nd edition) that chapter house of Fengheld is in Cherbourg.
I guess that the Normady tribunal will simply aknowledge the magsa as being an independent maga, with the hosue as her sanctum, but that they will not aknowledge her as being able to claim vis sites in the name of fengheld or other similar trans-border authority invasion
That particular Chapter House is in Cherbourg. According to The Lion and the Lily there is only one magus there. Given the rules of that Tribunal, she is a cenobite, and is limited to not being able to legally own any vis sources. She may lease vis sources if any are available or if she places well at the Tourney. The Lion and the Lily does have her harvesting certain vis sources, and leaves it as a problem for player magi of Confluensis to solve...
Bottom line, the rules for residency within the Tribunal will dictate how vis is apportioned. In Normandy, there are specific rules about who may "own" a vis source. All vis sources are actually owned by the Tribunal. Vis sources within 1 day round trip of a covenant generally belong to that covenant. Sources outside that range may be leased to a covenant, but that lease must be renewed at every Tribunal. Sources that require an element of danger/luck/chance/Hermetic Arts are open to any covenant to harvest. All sources must be registered.
A) a full covenant with a strong alliance to a covenant in another tribunal. Nothing wrong here, but the chapter house/covenant is 100% answerable as a normal covenant to the tribunal.
B) A hermit magus. In that case his ability to claim vis sources et al is subject to the legislation for hermit magi in the tribunal.
The fact that a covenant in another tribunal claim suzerainty over that covenant in your tribunal is a thing between the 2 covenants to decide, but in any case it is a thing of internal code.
It would depend on context. Where precisely is the "chapter house", what precisely are the magi doing, how powerful are the magi. Probably one of the following options:
a) Insist that the chapter house behaves as a normal legal covenant of the host Tribunal. I.e. it's all very well for the resident magi to claim that they are a chapter-house of Fengheld (or wherever), that is between them and Fengheld. As far as the host Tribunal is concerned the "chapter-house" has to obey whatever the normal rules of the Tribunal are for residency/establishing a covenant/vis-rights/etc. This seems to me to be the most likely option.
b) Treat the chapter house as part of its mother Tribunal. If it gets into legal difficulties with magi of the host Tribunal then the host Tribunal will (failing a negotiated settlement) take the issue to the Grand Tribunal just like it would for any other inter-Tribunal dispute. Probably, only viable if the chapter house is in an isolated part of the host Tribunal and geographically near to the covenants of its mother Tribunal. Remember that Tribunals are not really geographic territories, so there is scope for considerable ambiguity over which Tribunal some borderline covenants "should" belong to.
Cenobite. The most likely response IMO is to treat the chapter-house as an "invasion" of the foreign tribunal, and therefore consider it an illegal covenant. The rights of cenobite magi and their covenants are a matter for the local peripheral code but, in general, I'd say that they lack communal rights and protections, such as covenant-owned raw vis sources, a measure of protection of books and raw vis, and so on. Only a few tribunals will forbid all ownership of raw vis, or straight-out order the magi out of the tribunal.
[If the "chapter-house" is made up of one person, then treating him as an "Eremite"/lone-magus is theoretically an option, but in practice I think most tribunals accord respect to eremites that they would not extend to cenobites.]
Vassal. The chapter house will be treated as a full covenant of the tribunal, while recognizing that it owes certain "feudal" duties to its "lord", the mother-covenant at the foreign tribunal.
Commune. Perhaps the most interesting option is letting the covenant answer to the foreign-tribunal internally, but to the geographical tribunal in all its relations within the tribunal's region. You thus create an enclave of one tribunal within another. Things get extra-dicey when events transpire within the covenant but affect the host covenant (e.g. making money by magic and giving it out to a mundane middle-man).
Enemy of the Tribunal. Wizard war them to oblivion.
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