U.S. Acquisition of Guam in the Spanish-American War

Yes. The United States captured Guam from Spain during the Spanish–American War in 1898.

Guam was a Spanish colony. U.S. forces landed unopposed (Spanish garrison unaware war had started). The Treaty of Paris (1898) formally ceded Guam, along with Puerto Rico and the Philippines, to the United States.

Guam remains a U.S. territory and strategic military base in the Pacific.