bey vs merchant prince

bey

noun
  • in various other places, a prince or nobleman 

  • A governor of a province or district in the Turkish dominions 

merchant prince

noun
  • A prince among merchants: a wealthy and influential merchant. 

  • A mercantile plutocrat: a man who wields great de facto political power by virtue of economic assets derived from trade and commerce. 

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