despotism vs severity

despotism

noun
  • government by a singular authority, either a single person or tight-knit group, which rules with absolute power, especially in a cruel and oppressive way. 

severity

noun
  • The degree of something undesirable; badness or seriousness. 

  • The state of being severe. 

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