chieftain vs overseer

chieftain

noun
  • A leader of a clan or tribe. 

  • A leader of a group. 

overseer

noun
  • The manager of a plantation of slaves. 

  • An officer responsible for the care of the poor, making out lists of voters and those who had not paid taxes, etc. 

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