legation vs mission

legation

noun
  • The official residence of a diplomat. 

  • The purpose for which a legate is sent; a legate's mission or commission. Now rare (cf. OED) 

  • The post or office of a legate; a legateship. 

  • A diplomatic mission. 

mission

noun
  • A number of people appointed to perform any service; a delegation; an embassy. 

  • Religious evangelism. 

  • An infrequent gathering of religious believers in a parish, usually part of a larger regional event with a central theme. 

  • A settlement or building serving as a base for missionary work. 

  • A set of tasks that fulfills a purpose or duty; an assignment set by an employer, or by oneself. 

  • Third World charities, particularly those which preach as well as provide aid. 

verb
  • To do missionary work, proselytize. 

  • To send on a mission. 

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