When Allied armies were fighting their way off the Normandy beaches and into Nazi-occupied France 75 years ago, another battle raged in the Pacific that proved to be one of the pivotal US victories of World War II -- the Battle of Saipan.

The battle -- June 19 to July 9, 1944 -- saw the United States gain important airstrips that enabled the bombing of the Japanese main islands, an event some have called the "death knell" for Tokyo's war effort.

The fight for Saipan, in the Mariana Islands, took a high toll on both sides. Some 29,000 Japanese troops, almost the entire force Tokyo put on the island, were killed. Thousands of Japanese civilians also died, hundreds of them jumping to their deaths from cliffs rather than be captured by the Americans. US losses totaled almost 3,000 dead and more than 10,000 wounded.

A US soldier pushes a baby carriage while escorting a family to an internment camp during the Battle of Saipan.
A US soldier pushes a baby carriage while escorting a family to an internment camp during the Battle of Saipan.
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Imperial Japanese Army Capt. Sakae Oba surrenders his sword to Lt. Col. Howard C. Kurgis.
Imperial Japanese Army Capt. Sakae Oba surrenders his sword to Lt. Col. Howard C. Kurgis.
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Army reinforcements wade ashore on Saipan without enemy opposition. They relieved Marines in the battle of attrition raging in the island's interior. The ships of Task Force 58 are behind them in the Pacific Ocean.
Army reinforcements wade ashore on Saipan without enemy opposition. They relieved Marines in the battle of attrition raging in the island's interior. The ships of Task Force 58 are behind them in the Pacific Ocean.
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A father sits on the ground with his wounded child after the battle between US and Japanese forces for control of Saipan, Northern Marianas Islands in July 1944.
A father sits on the ground with his wounded child after the battle between US and Japanese forces for control of Saipan, Northern Marianas Islands in July 1944.
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Smoke and flames pour from ruins of buildings hit during a fierce battle to take Saipan from occupying Japanese forces.
Smoke and flames pour from ruins of buildings hit during a fierce battle to take Saipan from occupying Japanese forces.
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Smoke rises into the sky from the US artillery and naval bombardment of a Japanese seaplane base at Flores Point, near Tanapag Harbor.
Smoke rises into the sky from the US artillery and naval bombardment of a Japanese seaplane base at Flores Point, near Tanapag Harbor.
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US Marines crawl on the beach to avoid Japanese gunfire after landing on Saipan.
US Marines crawl on the beach to avoid Japanese gunfire after landing on Saipan.
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Planes from a Japanese fleet battle planes and ships of US Task Force 58 during operations off Saipan in the Marianas in 1944.
Planes from a Japanese fleet battle planes and ships of US Task Force 58 during operations off Saipan in the Marianas in 1944.
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A civilian family squats on the ground, surrounded by US Marines after the battle between US and Japanese forces for control of Saipan in July 1944.
A civilian family squats on the ground, surrounded by US Marines after the battle between US and Japanese forces for control of Saipan in July 1944.
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A group of B-29 bombers are in flight over the Pacific Ocean en route to Saipan, on January 15, 1945.
A group of B-29 bombers are in flight over the Pacific Ocean en route to Saipan, on January 15, 1945.
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Japanese POWs seen in an enclosure during the Battle of Saipan are some of the more than 900 who surrendered on Saipan.
Japanese POWs seen in an enclosure during the Battle of Saipan are some of the more than 900 who surrendered on Saipan.
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A US Marine rests behind a cart on a rubble strewn street during the battle to take Saipan from occupying Japanese forces on July 9, 1944.
A US Marine rests behind a cart on a rubble strewn street during the battle to take Saipan from occupying Japanese forces on July 9, 1944.
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'Dauntless Dottie,' one of America's B-29 Superfortress bombers, is made ready for a bombing run on Tokyo.
'Dauntless Dottie,' one of America's B-29 Superfortress bombers, is made ready for a bombing run on Tokyo.
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With dead Japanese soldiers nearby, Marines aim at the enemy during the US invasion of Saipan.
With dead Japanese soldiers nearby, Marines aim at the enemy during the US invasion of Saipan.
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