Londinium vs United Kingdom of Great Britain

Londinium

name

  • Synonym of Modern London A city in England, United Kingdom 

  • A city in Britannia, Roman Empire An ancient settlement in the area of modern London. 

United Kingdom of Great Britain

name

  • the Kingdom of Great Britain 

  • United Kingdom 

How often have the words Londinium and United Kingdom of Great Britain occurred in a corpus of books? (source: Google Ngram Viewer )