mission vs occupation

mission

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

  • Religious evangelism. 

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

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

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

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

verb
  • To do missionary work, proselytize. 

  • To send on a mission. 

occupation

noun
  • An activity or task with which one occupies oneself; usually specifically the productive activity, service, trade, or craft for which one is regularly paid; a job. 

  • The act, process or state of possessing a place. 

  • The control of a country or region by a hostile military and/or paramilitary force. 

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