abdicate vs turn one's coat

abdicate

verb
  • To relinquish or renounce a throne, or other high office or dignity; to renounce sovereignty. 

  • To surrender, renounce or relinquish, as sovereign power; to withdraw definitely from filling or exercising, as a high office, station, dignity; to fail to fulfill responsibility for. 

turn one's coat

verb
  • To turn against a previous affiliation or allegiance. 

  • Used other than figuratively or idiomatically: see turn, coat. 

How often have the words abdicate and turn one's coat occurred in a corpus of books? (source: Google Ngram Viewer )