oppression vs subjection

oppression

noun
  • The act of oppressing, or the state of being oppressed. 

  • The exercise of authority or power in a burdensome, cruel, or unjust manner. 

  • A feeling of being oppressed. 

subjection

noun
  • The state of being subjected. 

  • The act of bringing something under the control of something else. 

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