dictatorship vs sovereigndom

dictatorship

noun
  • A type of government where absolute sovereignty is allotted to an individual or a small clique. 

  • Any household, institution, or other organization that is run under such sovereignty or autocracy. 

  • A government which exercises autocratic rule. 

sovereigndom

noun
  • The state, condition, or realm of a sovereign; sovereignty. 

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