minister-president vs sachem

minister-president

noun
  • The head of government in a number of European countries or subnational governments, in which a parliamentary or semi-presidential system of government prevails, who presides over the council of ministers. 

sachem

noun
  • A boss, a leader. 

  • A chief of one or several Native American tribe(s), especially of the Algonquians; a sagamore. 

  • A high-ranking officer of the Tammany Hall political organization. 

How often have the words minister-president and sachem occurred in a corpus of books? (source: Google Ngram Viewer )