dictatorial vs imperious

dictatorial

adj
  • in the manner of a dictator, usually with callous disregard for others. 

  • of or pertaining to a dictator 

imperious

adj
  • Domineering, arrogant, or overbearing. 

  • Urgent. 

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