In Cuba a second war of independence erupted in 1895 after it had failed to gain freedom from Spain in the Ten Years’ War (1868–1878). A brutal war of attrition ensued, and by 1898 the countryside was in ruins and Spanish colonial control was restricted to a handful of cities. Cuban nationalists were on the verge of defeating the Spanish forces and gaining independence. But before they could realize this goal, the United States intervened.

The U.S. intervention began with a provocative act: sailing the battleship Maine into Havana harbor. This was an aggressive act because the battleship was capable of bombarding the entire city. But soon after it laid anchor, the Maine exploded and sank, killing hundreds of sailors. The U.S. government accused Spain of sinking the warship, a charge Spain denied, and demanded that the Spanish government provide restitution. Regardless of the cause, the sinking of the Maine led to war between Spain and the United States over control of Cuba and the Philippines. From April to August 1898 the U.S. Navy and Marines fought and defeated Spanish forces in the Pacific and the Caribbean. With its victory, the United States acquired Guam and Puerto Rico and launched a military occupation of Cuba and the Philippines.

Puerto Rico and Guam became colonies directly ruled by U.S. administrators, and residents of both island territories did not gain the right to elect their own leaders until after the Second World War. They remained commonwealths (territories that are not states) of the United States. The U.S. government also established direct rule in the Philippines, brushing aside the government established by Filipino nationalists who had fought for freedom from Spain. Nationalists then fought against the Unites States in an unsuccessful effort to establish an independent government in the Philippine-American War (1899–1902).

Cuba alone gained formal independence, but U.S. pressure limited that independence. The Platt Amendment, which the United States imposed as a condition of Cuban independence, gave the United States the power to cancel laws passed by the Cuban congress, withheld the Cuban government’s right to establish foreign treaties, and granted the United States control over Guantanamo Bay, where it established a permanent naval base. Moreover, the United States militarily occupied Cuba in 1899–1902, 1906–1908, and 1912. Between 1917 and 1922 U.S. administrator Enoch Crowder governed the island.

The constraints that the U.S. government imposed on Cuban politics, along with its willingness to deploy troops and periodically establish military rule, created a safe and fertile environment for U.S. investment. By 1919 half of the island’s sugar mills were owned by U.S. businesses. Small farms were consolidated into massive estates as twenty-two companies took hold of 20 percent of Cuba’s national territory. U.S. companies like Coca-Cola and Hershey were among the new landowners that took control of their most important ingredient: sugar.

The United States imported its prevailing racial policies to its new Caribbean territories. In Cuba, U.S. authorities encouraged political parties to exclude black Cubans. Black war veterans established the Independent Party of Color in 1908 in order to press for political inclusion. The party was banned in 1910, and in 1912 its leaders organized a revolt that led to a violent backlash by the army and police, supported by U.S. Marines. The campaign against members of the party was followed by a wave of lynchings of black Cubans across the island.

In Puerto Rico the influence of U.S. racism was more direct. The United States carried out the involuntary sterilization of thousands of Puerto Rican women as part of a policy aimed at addressing what the government saw as overpopulation on the island. In addition, Puerto Rican men drafted into U.S. military service were organized into segregated units, as African Americans were.