Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

What is the only nation state of the Commonwealth of Nations on the mainland of South America?
commonwealth of nations

Which entertainer uses various names, including Puff Daddy, P. Diddy and Diddy?
p. diddy

Who succeeded Sir William Howe as Commander in Chief of the British forces in 1778 during the American War of Independence?

american revolutionary war