Drawing on some background from Faith and Flame, how about this backstory?
Bentalone was a rival of the Bellaquin covenant. It occupies a small fortress in a valley near Alés, on the lands of the de Montalet estates. The original site of Bellaquin was destroyed around 1199 (same year as the death of Arnault I Bérard de Montalet ); Bentalone was behind this? Note that there seems to be lots of shuffling around of titles within the family and with the bishop of Uzés around 1199-1202, which could well lead to Bentalone getting land independent of any lord.
That only lasted a few years and Bentalone was destroyed in 1206; perhaps Bellaquin was involved here?
In 1220, Arnault II Bérard is probably in his late twenties and is making moves to reclaim the land owned by Bentalone. This move explains why it's being re-founded now: a presence there may keep Arnault II from just taking the land unopposed.
The sponsoring covenants are Coenobium and Ostal des Exiles. They both have their own reasons for the alliance, mainly to influence the other covenant.
The Bentalone site still has a Magic aura, and some kind of affinity for Auram and Animal; it's the source of the bird-wing symbol of the Berard family.