instigator

a person who stirs up public feelings especially of discontent <an instigator who always managed to be innocently standing by once the fighting began> Synonyms demagogue (also demagog), exciter, firebrand, fomenter, incendiary, inciter, agitator, kindler, provocateur, rabble-rouserRelated Words demonstrator, marcher, objector, picketer, protester (or protestor); advocate, apostle, backer, booster, champion, exponent, persuader, promoter, proponent, reformer, reformist, supporter; alarmist, extremist, insurgent, insurrectionist, radical, rebel, revolter, revolutionary, revolutionist, subversive, troublemaker; goader, prodder, prompter, provoker; agent provocateurNear Antonyms peacemaker, reconciler, uniter