Qin vs Yuan

Qin

name

  • An ancient feudal state of China that existed between 778 and 207 BC. 

  • The first imperial dynasty of China, lasting from 221 to 207 BC. 

  • A surname from Chinese. 

  • A county of Changzhi, Shanxi, China. 

Yuan

name

  • The imperial dynasty of China from 1279 to 1368. 

  • A surname from Chinese. 

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