agitationist vs firebrand

agitationist

noun
  • Synonym of agitator (“one who stirs up or excites others, for example political reformers”) 

firebrand

noun
  • An argumentative troublemaker or revolutionary; one who agitates against the status quo. 

  • A torch or other burning stick with a flame at one end. 

How often have the words agitationist and firebrand occurred in a corpus of books? (source: Google Ngram Viewer )