in contention vs warring

in contention

prep
  • Used other than figuratively or idiomatically: see in, contention. 

  • Contending for a title or championship. 

warring

adj
  • engaged in war; belligerent 

noun
  • The act of engaging in war or conflict. 

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