Joseph Pulitzer and William Randolph Hearst were covering events in Cuba and how they were struggling for their independence. Both Pulitzer and Hearst started printing rousing stories that were false in order to obtain more profit. Pulitzer and Hearst had been selling papers by fanning t opinions of the anit-Spanish public, but in the early 1898 Pulitzer and Hearst got their big break when a U.S. battleship sunk in Havana Harbor during a planned visit of a Spanish ship to New York. On February 15 there was an explosion on the ship’s hull, that’s when Pulitzer and Hearst published rumors about the plots to sink the ship and the Yellow Journalism called for war after the U.S. naval investigation found the reason for the explosion thus starting the Spanish-American war.
https://history.state.gov/milestones/1866-1898/yellow-journalism
Yellow Journalism 