During the Japanese colonial era, roughly 400 Korean people, who were forced onto Battleship Island ("Hashima Island") to mine for coal, attempt to a dramatic escape.During the Japanese colonial era, roughly 400 Korean people, who were forced onto Battleship Island ("Hashima Island") to mine for coal, attempt to a dramatic escape.During the Japanese colonial era, roughly 400 Korean people, who were forced onto Battleship Island ("Hashima Island") to mine for coal, attempt to a dramatic escape.