There could be a number of reasons why the group has been assembled.
For example, an outside party is the reason the group has been assembled ...
The Heptagram wants to investigate the sorcerous properties of these new finds, and if there's a stock of First Age artifacts there, all the better.
The Deliberative has heard rumours of some new territory, and judges it unclaimed, therefore a party of loyal Dynasts shall go and plant the flag (preferably through the chest of any troublesome natives who want to argue that call), and expand the borders of the Realm.
The Guild hasn't been able to get a proper foothold, and wants to set things up to they control the flow of trade in and out of this new territory.
Depending on how any given House thinks, they might send their best, or their most expendible, in order to see their obligation met.
If we have a Sorcerer in the party, this could be their Obligation to the Realm, and they bring along their sworn brotherhood.