oligarchy vs peremptoriness

oligarchy

noun
  • Those who make up an oligarchic government. 

  • A state ruled by such a government. 

  • A government run by only a few, often the wealthy. 

peremptoriness

noun
  • The quality of being peremptory 

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