overwhelm vs unhorse

overwhelm

verb
  • To cause to surround, to cover. 

  • To overpower emotionally. 

  • To engulf, surge over and submerge. 

  • To overpower, crush. 

noun
  • The state or condition of being overwhelmed. 

unhorse

verb
  • To disrupt or unseat; to remove from a position. 

  • To forcibly remove from a horse. 

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