monarch

coruler

Caesar, czar (also tsar), emir (or amir), emperor, empress, kaiser, khan, khedive, king, lord, mikado, mogul, prince, queen, satrap, shah, sultan, suzerain

authoritarian, Big Brother, despot, dictator, führer (or fuehrer), monocrat, overlord, paramount, tyrant

big boy, big cheese, bigfoot, biggie, big gun, big shot, big wheel, bigwig, fat cat, figure, heavy, heavyweight, honcho, kahuna, main man, mover and shaker, nabob, nawab, notable, personage, pooh-bah (also poo-bah), supremo [chiefly British], VIP

celebrity, personality, star, superstar

deity, demigod, god