Question: what countries were involved in the battle of okinawa?
Answer: Battle of Okinawa, (April 1–June 21, 1945), World War II battle fought between U.S. and Japanese forces on Okinawa, the largest of the Ryukyu Islands. Okinawa is located just 350 miles (563 km) south of Kyushu, and its capture was regarded as a vital precursor to a ground invasion of the Japanese home islands.