The Japanese suffered roughly 21,000 dead. Out of the 23,000 Japanese on the island only 1,083 were taken prisoner. 2 Japanese did not surrender until 1951. 27 Medals of Honor were awarded to Americans during the 36 days of the battle.
American losses included 5,900 dead and 17,400 wounded.
The Japanese fought from an elaborate network of caves, dugouts, tunnels, and underground installations that were difficult to find and destroy.
The American amphibious invasion of Iwo Jima, a key island in the Bonin chain roughly 575 miles from the Japanese coast, was sparked by the desire for a place where B-29 bombers damaged over Japan could land without returning all the way to the Marianas, and for a base for escort fighters that would assist in the bombing campaign. (History.Com)