peaceful vs relentless

peaceful

adj
  • Motionless and calm. 

  • Inclined to peace. 

  • Not at war; not disturbed by strife or turmoil. 

noun
  • a Muslim; especially a violent member of a radical Islamist group. 

relentless

adj
  • Unremitting, steady and persistent. 

  • Unrelenting or unyielding in severity. 

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