assign_landed_realm_priest_effect

assign_landed_realm_priest_effect = {
	save_temporary_scope_as = realm_priest_liege

	if = {
		limit = {
			capital_county.clerical_region_title.holder ?= {
				can_be_landed_realm_priest_trigger = { COURT_OWNER = scope:realm_priest_liege }
			}
		}
		capital_county.clerical_region_title.holder = {
			save_temporary_scope_as = chosen_realm_priest
		}
	}
	else_if = {
		limit = {
			any_vassal = {
				can_be_landed_realm_priest_trigger = { COURT_OWNER = scope:realm_priest_liege }
				capital_county.clerical_region_title.holder ?= this
			}
		}
		ordered_vassal = {
			limit = {
				can_be_landed_realm_priest_trigger = { COURT_OWNER = scope:realm_priest_liege }
				capital_county.clerical_region_title.holder ?= this
			}
			order_by = capital_county.clerical_region_title.clerical_region_size
			position = 0
			save_temporary_scope_as = chosen_realm_priest
		}
	}
	else_if = {
		limit = {
			faith.religious_head ?= {
				can_be_landed_realm_priest_trigger = { COURT_OWNER = scope:realm_priest_liege }
			}
		}
		faith.religious_head = {
			save_temporary_scope_as = chosen_realm_priest
		}
	}
	else_if = {
		limit = {
			any_vassal = {
				can_be_landed_realm_priest_trigger = { COURT_OWNER = scope:realm_priest_liege }
			}
		}
		ordered_vassal = {
			limit = {
				can_be_landed_realm_priest_trigger = { COURT_OWNER = scope:realm_priest_liege }
			}
			order_by = learning
			position = 0
			save_temporary_scope_as = chosen_realm_priest
		}
	}

	# We check again because scope:chosen_realm_priest can still be set from an earlier council owner
	# Skip an already seated pick so repeat calls do not cycle the seat
	if = {
		limit = {
			exists = scope:chosen_realm_priest
			scope:chosen_realm_priest = {
				can_be_landed_realm_priest_trigger = { COURT_OWNER = scope:realm_priest_liege }
			}
			NOT = { cp:councillor_court_chaplain ?= scope:chosen_realm_priest }
		}
		assign_councillor_type = {
			type = councillor_court_chaplain
			remove_existing_councillor = yes
			target = scope:chosen_realm_priest
		}
	}
}

As written in game/common/scripted_effects/00_councillor_effects.txt.