The Spanish-American War was the result of US involvement in Cuba's battle for independence from Spain. Publishers such as William Randolph Hearst and Joseph Pulitzer used their newspapers to criticize Spain.
The mysterious sinking of the US battleship Maine in Havana Harbor in February 1898 was blamed on Spain by the press. War was declared and US troops sent to Cuba. Among the units sent was the "Rough Riders," organized by Theodore Roosevelt. The Rough Riders gained their fame at the Battle of San Juan Hill.
The ten week war resulted in the US gaining control of a number of Spanish possessions.
Read on: https://en.wikipedia.org/wiki/Spanish%E2%80%93American_War
Family connections: My great-grandmother's brother was supposed to have fought with TR at San Juan Hill, but the story didn't pan out. John W. Simmons did however become involved in the Philippines. [next post!]