backwoodsman vs frontiersman

backwoodsman

noun
  • A person who is acclimated to living in a forest area that is far removed from civilization or modern conveniences. 

  • An uncivilized person. 

  • A Peer who is seldom present in the House of Lords of the United Kingdom Parliament, who may be encouraged to attend when a very important vote is expected. 

frontiersman

noun
  • A person who lives on the borders of a country, or in a wild and undeveloped area on the fringes of civilization. 

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