Operation Iceberg, historically known as Battle of Okinawa, lasted 82 days, from 1, April to June, 22, on 1945. At the allied side 20.195, soldiers were killed. In the Japanese side, the estimatives range from 77.000 to 110.000. The Okinawa Prefecture estimates civilian loss in over 100.000.
Keegan: The Times Atlas of the Second World War. 1989