The Spanish-American War ( 1898 ) ended Spanish colonial rule in the Americas. It originated in the Cuban struggle for independence from Spain. The battleship USS Maine was sent to protect US citizens after anti-Spanish rioting in Havana. The Maine had misteriosly sunk in Havana harbor and the US blamed Spain for this tragedy. In April 1898, the US congress supported total Cuban independence and after that bth sides declared war. Answer: B. The explosion of the American battleship the Maine.