The brief and one-sided Spanish-American War comes to an end when Spain formally agrees to a peace protocol on U.S. terms: the cession of Cuba, Puerto Rico and Manila in the Philippines to the United States pending a final peace treaty.

The Spanish-American War had its origins in the rebellion against Spanish rule that began in Cuba in 1895. The repressive measures that Spain took to suppress the guerrilla war, such as herding Cuba’s rural population into disease-ridden garrison towns, were graphically portrayed in U.S. newspapers and enflamed public opinion. In January 1898, violence in Havana led U.S. authorities to order the battleship USS Maine to the city’s port to protect American citizens. On February 15, a massive explosion of unknown origin sank the Maine in the Havana harbor, killing 260 of the 400 American crewmembers aboard. An official U.S. Naval Court of Inquiry ruled in March, without much evidence, that the ship was blown up by a mine but did not directly place the blame on Spain. Much of Congress and a majority of the American public expressed little doubt that Spain was responsible, and called for a declaration of war.

In April, the U.S. Congress prepared for war, adopting joint congressional resolutions demanding a Spanish withdrawal from Cuba and authorizing President William McKinley to use force. On April 23, President McKinley asked for 125,000 volunteers to fight against Spain. The next day, Spain issued a declaration of war. The United States declared war on April 25. On May 1, the U.S. Asiatic Squadron under Commodore George Dewey destroyed the Spanish Pacific fleet at Manila Bay in the first battle of the Spanish-American War. Dewey’s decisive victory cleared the way for the U.S. occupation of Manila in August and the eventual transfer of the Philippines from Spanish to American control.

On the other side of the world, a Spanish fleet docked in Cuba’s Santiago harbor in May after racing across the Atlantic from Spain. A superior U.S. naval force arrived soon after and blockaded the harbor entrance. In June, the U.S. Army Fifth Corps landed in Cuba with the aim of marching to Santiago and launching a coordinated land and sea assault on the Spanish stronghold. Included among the U.S. ground troops were the Theodore Roosevelt-led “Rough Riders,” a collection of Western cowboys and Eastern blue bloods officially known as the First U.S. Voluntary Cavalry. On July 1, the Americans won the Battle of San Juan Hill, and the next day they began a siege of Santiago. On July 3, the Spanish fleet was destroyed off Santiago by U.S. warships under Admiral William Sampson, and on July 17 the Spanish surrendered the city—and thus Cuba—to the Americans.

In Puerto Rico, Spanish forces likewise crumbled in the face of superior U.S. forces, and on August 12 an armistice was signed between Spain and the United States. On December 10, the Treaty of Paris officially ended the Spanish-American War. The once-proud Spanish empire was virtually dissolved, and the United States gained its first overseas empire. Puerto Rico and Guam were ceded to the United States, the Philippines were bought for $20 million, and Cuba became a U.S. protectorate. Philippine insurgents who fought against Spanish rule during the war immediately turned their guns against the new occupiers, and 10 times more U.S. troops died suppressing the Philippines than in defeating Spain.