You don't actually need a trigger, do it when the faction changes from
. script_game_start calls script_give_center_to_faction_aux instead so you don't have to worry about it starting with the wrong name. Same goes with faction name changes, although you could add a delay and check when they've conquered a town in
which gets called quite often.
Code:
script_give_center_to_faction
Code:
script_faction_recalculate_strength