rulership vs sovereignty

rulership

noun
  • A position in which one rules or has sovereignty over others. 

sovereignty

noun
  • An independent or sovereign territory. 

  • Of a polity: the state of making laws and controlling resources without the coercion of other nations. 

  • Of a ruler: supreme authority over all things. 

  • Of a person: the liberty to decide one's thoughts and actions. 

  • Excellence, mastery, preeminent efficacy. 

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