治者 is read as ちしゃ (chisha) and means ruler.
ちしゃ
chisha
とうちしゃ
the ruler
せいじてきしどうしゃ
political leader
ちあん
public order
なおる
to get better
おさまる
to be at peace
おさめる
to subdue
なおす
to cure
ちすい
river management
ちけん
clinical trial
ちさん
forest conservation
なおり
recovery
ちがいほうけん
extraterritoriality