Hearts of Iron is a 2002 grand strategy computer game developed by Paradox Development Studio and published by Strategy First. It was released for Microsoft Windows on November 24, 2002. A Mac OS version was also later released by Virtual Programming. Set in the years 1936-1948, players are able to control any one nation as World War II unfolds, and form alliances with other nations. There are three sequels to Hearts of Iron; Hearts of Iron II, Hearts of Iron III, Hearts of Iron IV.