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(Friday, June 22, 1945, 10:00 a.m. Japan Standard Time; during the Battle of Okinawa, part of the Pacific Theatre of World War II) — One of the most brutal and hard-fought campaigns of the Pacific war drew to a close today as American forces secured the island of Okinawa after nearly three months of combat.

The battle, which began with an amphibious landing on April 1, 1945, stands as the largest and longest operation in the Pacific Theater of this war. Today’s conclusion marks the end of 82 days of bitter fighting, which U.S. commanders say cost the Japanese more than 100,000 men.

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American casualties have also been severe, with at least 50,000 killed, wounded, or missing in action.

The assault, codenamed Operation Iceberg, involved a massive Allied force under the newly formed U.S. Tenth Army — a joint Army-Marine command consisting of four Army divisions and three Marine divisions, backed by an unprecedented air, sea, and land effort.

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The Tenth Army, commanded by Lt. Gen. Simon Bolivar Buckner Jr., who was killed in action just days ago, operated with its own tactical air force and support from a vast naval fleet.

Opposing the Allied advance was Japan’s Thirty-Second Army, led by Lt. Gen. Mitsuru Ushijima, who is believed to have taken his own life as defeat became inevitable. His forces, made up of regular army units, naval personnel, and large numbers of conscripted Okinawan civilians, fought fiercely across the island’s rocky terrain, caves, and ridges.

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The campaign, described by troops as a “typhoon of steel,” saw relentless kamikaze attacks on Allied ships, with the Japanese losing hundreds of planes and dozens of vessels, including the giant battleship Yamato, sunk during a desperate sortie in April.

The United States Navy also suffered heavy losses, with many vessels damaged or destroyed in the suicide raids.

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Local Okinawan civilians were caught in the crossfire, and reports from military authorities and civilian officials indicate that well over 100,000 native islanders may have perished in the fighting — many of them victims of forced suicide or killed while defending Japanese positions.

With Okinawa now in American hands, the island’s airfields and deepwater ports are expected to serve as critical launching points for the final stage of the war in the Pacific.

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Military planners are already preparing for what is expected to be the most ambitious operation of the war: a direct invasion of the Japanese home islands.