<P> Puerto Rico , Guam , and the Philippines ( for which the United States compensated Spain $20 million , equivalent to $588 million in present - day terms ) , were ceded by Spain after the Spanish -- American War in the 1898 Treaty of Paris . Spain relinquished all claim of sovereignty over Cuba , but did not cede it to the United States , so it became a protectorate . All four of these areas were under United States Military Government ( USMG ) for extended periods . Cuba became an independent nation in 1902 , and the Philippines became an independent nation in 1946 . </P>
when did the united states acquired puerto rico
after the Spanish -- American War in the 1898 Treaty of Paris