Which major Pacific War battle ended on 22 June 1945, shortly before Japan surrendered?

The major Pacific War battle that ended on 22 June 1945 was the Battle of Okinawa.

The Battle of Okinawa was fought from 1 April to 22 June 1945, making it the largest amphibious assault of the Pacific War. U.S. forces landed on Okinawa to secure airfields and a base close enough to support operations against the Japanese home islands.

Japanese forces used fortified positions, artillery, kamikaze attacks, and underground defenses. Fighting was especially severe in the southern part of the island, where civilian casualties were also extensive. Lieutenant General Simon Bolivar Buckner Jr., commander of the U.S. Tenth Army, was killed near the end of the battle.

Okinawa’s high casualties influenced Allied planning for a possible invasion of Japan. However, the battle was not the final fighting involving Japanese forces: combat continued elsewhere in Asia and the Pacific until Japan’s formal surrender in September. The island remained under U.S. administration until 1972.