The only cast member to be in both this film and its companion piece, Flags of Our Fathers (2006), appears in the flamethrowing image of Chuck Lindberg (played by Alessandro Mastrobuono). He advances on a bunker with a flamethrower. Individual members of the casts of both films have met, though never officially presented together, as there are commonalities between the casts in the acting community.
Ken Watanabe read actual letters sent by Imperial Japanese Army Gen. Tadamichi Kuribayashi to his family from Iwo Jima while preparing for his role.
The story of Lt. Ito strapping mines to himself and lying among corpses to attack a tank is based on the real-life story of Satoru Omagiri, as told in "The Rising Sun" by John Toland.
Kazunari Ninomiya, who played Saigo, is a part of the Japanese pop boy-band Arashi.
General Tadamichi Kuribayashi's pistol is a Colt M1911A1 with white ivory grips. The pistol was designed by John M. Browning in 1911 and was the US sidearm all the way up to 1986.
The last foreign language film to date to be nominated for an Academy Award for Best Picture (Japanese).