bring to heel vs conquer

bring to heel

verb
  • To compel someone to obey; to force someone into a submissive condition. 

  • To cause to act in a disciplined manner. 

conquer

verb
  • To defeat in combat; to subjugate. 

  • To overcome an abstract obstacle. 

  • To acquire by force of arms, win in war; to become ruler of; to subjugate. 

How often have the words bring to heel and conquer occurred in a corpus of books? (source: Google Ngram Viewer )