chatelain vs seneschal

chatelain

noun
  • Synonym of castellan: the lord of a castle; a caretaker entrusted to oversee a castle for its lord. 

seneschal

noun
  • A steward, particularly (historical) one in charge of a medieval nobleman's estate. 

  • An officer of the crown in late medieval and early modern France who served as a kind of governor and chief justice of the royal court in Normandy and Languedoc. 

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