flag-bearer vs guidon

flag-bearer

noun
  • One who carries a flag, especially at a ceremony. 

  • One who openly promotes an idea or value and becomes symbolic for it. 

guidon

noun
  • A soldier assigned to carry such a banner. 

  • A small pennant or banner carried by infantry soldiers to direct troop movement. 

How often have the words flag-bearer and guidon occurred in a corpus of books? (source: Google Ngram Viewer )