The notable military conflict that involved the Spanish Empire and the United States was the Spanish-American War, which occurred in 1898. The war was driven by various factors, including the explosion of the USS Maine in Havana Harbor and growing American interests in Cuban independence from Spanish rule. The conflict lasted about four months, resulting in a decisive victory for the United States. As a consequence, Spain ceded territories such as Puerto Rico, Guam, and the Philippines to the U.S. This conflict marked a significant shift in U.S. foreign policy, as the nation began to take on a more imperialistic role on the global stage.