Seavey's Island side of Seavey's Island at the former site of Camp Long, a stockade named for Secretary of the Navy John Long, where 1,612 prisoners of war from the Battle of Santiago de Cuba were confined from July 11 to mid-September 1898 during the Spanish–American War. Camp Heywood, a Marine camp named after Colonel Charles Heywood, was located just north of the naval prison. It was occupied after the 1st Battalion's return from Cuba in late August until September 21, 1898. According to the National Trust for Historic Preservation, the Portsmouth Naval Shipyard has 62 buildings listed on the National Register
Battle of Santiago de Cuba Spanish government sent their fleet under Admiral Pascual Cervera y Topete to defend Cuba and keep an open line of communication with the Spanish garrison there; Cervera opposed this strategy. He believed his squadron lacked the strength necessary to engage the American squadron, preferring instead to engage the Americans near the Canary Islands or to mount an attack against the American coast, but he was overruled by his superiors in Madrid. Cervera's own misgivings reveal the seriousness of the situation faced: Lacking a clear strategy, the Spanish may have hoped to end the war quickly in a "glorious defeat" against