A conflict between Spain and the USA. It had its roots in the struggle for independence of Cuba, and in US economic and imperialist ambitions. Sympathetic to Cuban rebels whose second war of independence against Spain had begun in 1895, the USA used the mysterious blowing up of its battleship, the Maine, in Havana harbour as a pretext for declaring war. The Spanish navy suffered serious defeats in Cuba and the Philippines, and a US expeditionary force (which included the future President Theodore Roosevelt and his Rough Riders) defeated Spanish ground forces in Cuba and in Puerto Rico. Spain surrendered at the end of 1898, Puerto Rico being ceded to the USA and Cuba placed under US protection. The Pacific island of Guam was also ceded while the Philippines were bought by the USA for $20 million. The war signalled the emergence of the USA as an important world power as well as the dominant power in the Caribbean.