authoritarian

arrogant, assumptive, disdainful, fastuous, haughty, highfalutin (also hifalutin), high-and-mighty, high-hat, huffy, important, lofty, lordly, overweening, presuming, presumptuous, pretentious, proud, self-asserting, supercilious, superior, toplofty (also toploftical), uppish, uppity

commanding, controlling, dictating, regimental

arbitrary, high-handed, imperial

directorial, magisterial

aggressive, assertive, self-assertive

imperative

conceited, narcissistic, pompous, vain

all-powerful, almighty, omnipotent

firm, stern

demanding, exacting

uncharitable, unforgiving

adamant, callous, hardened, hard-hearted, hard-line, immovable, implacable, inflexible, merciless, pitiless, relentless, rock-ribbed, stiff, unbending, uncompromising, unrelenting, unsparing, unyielding

dour, gruff

ascetic (also ascetical), monastic, monkish

browbeating, bullying