The primary outcome of the Spanish-American War in 1898 was the significant expansion of the United States' territorial holdings. The war resulted in the defeat of Spain and relinquishment of its colonies, including Puerto Rico, Guam, and the Philippines to the U.S. This marked a transition in U.S. foreign policy, as it stepped onto the global stage as an imperial power. The Treaty of Paris, signed in December 1898, formalized the U.S. gains and raised questions about the future of imperialism and American identity in the context of expansion.