auteur vs essayist

auteur

noun
  • A creative artist, especially a film director, seen as having a specific, recognisable artistic vision, and who is seen as the single or preeminent ‘author’ of his works. 

essayist

noun
  • One who composes essays; a writer of short compositions. 

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