Potentate

n.

1.

One who is potent; one who possesses great power or sway; a prince, sovereign, or monarch. The blessed and only potentate. - 1 Tim. vi. 15. Cherub and seraph, potentates and thrones. - Milton.

Noun

1.

potentate - a ruler who is unconstrained by law Synonyms: dictator

POTENTATE. One who has a great power over, an extended country; a sovereign.
     2. By the naturalization laws, an alien is required, before he can be naturalized, to renounce all allegiance and fidelity to any foreign prince, potentate, state, or sovereign whatever.

anointed king, chief, chieftain, crowned head, dynast, emperor, grand duke, high chief, imperator, king, king-emperor, kinglet, lord paramount, majesty, monarch, overlord, paramount, petty king, prince, prince consort, royal, royal personage, royalty, ruler, sovereign, suzerain, tetrarch