Some other examples:

  • Prime Minister of the United Kingdom
  • President of Russia
  • President of the Russian Federation
  • Emperor of Japan

marked as duplicate by Mari-Lou A, Edwin Ashworth, AmE speaker, choster, RaceYouAnytime Apr 5 '18 at 19:09

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  • Although the linked question above is closed, I find the answers clearer to read, simple and more relevant to your case than the canonical question and its answers: Using the definite article before a country/state name – Mari-Lou A Apr 5 '18 at 11:01
  • Tsar of All the Russias – GEdgar Apr 5 '18 at 11:22
  • Both do and neither does, depending on the context. "The President is George Washington" gets its article from the phrase’s position in the sentence, not his position in society. Whether "George Washington is President" needs an article can't be clear without context. Any president, of a country or a mere corporation, sometimes does and sometimes doesn't warrant an article… in English. Am I mistaken in thinking Russian doesn't use articles, and doesn’t that make the concept strange, at least? – Robbie Goodwin Apr 5 '18 at 11:43
  • 2
    @RobbieGoodwin when a country is called a republic or is a collection of unified states or territories the definite article is always used. The United Kingdom, the USA, the United Arab Emirates, the ex-USSR, the Republic of China. The question is about the use of articles with a country's name not about its leader, or his or her position. You could have also said "Sarkozy was Prime Minister" No article there. – Mari-Lou A Apr 5 '18 at 11:51
  • The Question was clearly about the leader’s positions, not the country’s name. You seem to be suggesting “a union of ” means “a collection of unified”. What did I miss, please? Is the United States of America, or of Mexico “a collections of unified states or territories”?Underneath any of that, the Question was about not the states but rather, their presidents. Of course it’s the United Kingdom, the USA, the United Arab Emirates. It might be the Republic of China but that’s outside my ken… So what? The Question was clearly about the leader and his or her positions, not the country’s name. – Robbie Goodwin Apr 6 '18 at 19:57