unapologetic vs unrepentant

unapologetic

adj
  • Not apologetic for having said or done something that causes actual or potential harm, especially when being apologetic would be appropriate. 

unrepentant

adj
  • Feeling or showing no sorrow or regret for wrongdoing. 

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