Facts, information and articles about Battle Of Saipan, a battle of World War II

Battle Of Saipan Facts


15 June – 9 July 1944


Saipan, Mariana Islands


Allies:Richmond K. Turner
Holland Smith
Japanese:Yoshitsugu Saito
Chuichi Nagumo
Takeo Takagi
Matsuji Iluin

Soldiers Engaged

Allies: 71, 000
Japanese: 31, 000


American Victory


Allies: 3,426 killed and 10,364 wounded
Japanese: 24,000 killed, 5,000 suicides and 921 prisoners
22,000 civilians dead (mostly suicides)

Battle of Saipan Articles

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Battle Of Saipan summary: Possession of the island of Saipan in the Northern Marianas island chain became a critical objective for American forces during World War II in order to place the Japanese home islands within the flight range of the new B-29 Superfortress bombers. The Saipan battle began with a naval bombardment on June 13, 1944. Over the course of two days a total of 37 warships, including 15 battleships, fired more than 180,000 shells of various calibers at the island, the largest being 16-inch shells. Naval aircraft added their bombs to the attack. Despite this severe pounding, damage among the Japanese defenders was minimized by the defensive positions they had created, and some Japanese positions had not been identified by American planners. Some 15,000 Japanese army and navy personnel were believed to be on the island; in reality, the total was about twice that number. Additionally, the battle would be the first time Allied forces in the Pacific had to contend with a large civilian population; hundreds of families jumped off cliffs into the sea rather than surrender.

The Landings On Saipan

Landings started at 7 am on the 15th of June. Over 300 LVTs and 8,000 Marines landed on Saipan’s west coast. Eleven warships provided fire support for the invading troops..

The Battle for Saipan

The Japanese had cleverly marked the bay with flags to demarcate the shooting range. That allowed them to destroy almost 20 amphibious tanks. They also installed barbed wire, machine gun emplacements and trenches. This greatly increased American casualties. Despite the casualties the Marines had taken the beachhead by nightfall. The Japanese responded by counter attacking at night which resulted in them losing many men.

On the 16th of June the 27th Infantry Division landed and pushed towards the airfield at As Lito. The Japanese responded by attacking at night once again producing results that forced Saito to abandon the airfield. The attack at As Lito came as a surprise to the Japanese high command as they expected attacks to be focused further south. On the 15th of June the Japanese attacked at the Philippine Sea. The battle resulted in huge losses for the Japanese as they lost 3 aircraft carriers and hundreds of planes. On July 7, some 4,000 Japanese troops, realizing they could not hold out much longer, mounted the largest banzai charge of the war. Virtually all the attackers were killed, but two battalions of the U.S. Army’s 105th Infantry Regiment, 27th Infantry Division, were also decimated.


Featured Article About The Battle Of Saipan

Battle of Saipan

In the early morning hours of July 7, 1944, Lieutenant Colonel William J. O’Brien, commander of the 1st Battalion, 105th Infantry Regiment, 27th Infantry Division, was killed in action at Saipan during a massive Japanese suicide attack. His last words were: ‘Don’t give them a damned inch! It was a gyokusai attack–a suicidal assault ordered by Imperial General Headquarters in which each Japanese soldier on the island was meant to die for the emperor and, in dying, was supposed to kill seven Americans. The Japanese were ordered to take no prisoners.

The gyokusai attack on the Tanapag plain has been described by many historians of World War II as the most devastating attack by the Japanese during the war. For his heroic conduct during that battle, Colonel O’Brien was awarded the Medal of Honor posthumously. One of his soldiers, Sergeant Thomas A. Baker, who was also killed in the battle, was posthumously awarded the Medal of Honor, as well.

Saipan is one of the islands in the Marianas chain, about 1,300 miles south of the Japanese home islands. It is a small, pistol-shaped island about 5 miles wide and 18 miles long, which had tremendous strategic value for the United States. First, Saipan straddled the major supply routes between the Japanese home islands and the Japanese garrisons in the Central Pacific; second, its airfields provided a major staging area for Japanese air attacks on the American fleet operating in the Central Pacific; and third, its occupation by the Americans would provide a base from which to launch air attacks against Tokyo and the Japanese home islands.

Indeed, the nearby island of Tinian would later serve as the base of operations for the planes that dropped atomic bombs on Hiroshima and Nagasaki in August 1945. Those attacks led to the unconditional surrender of Japan and eliminated the need for an all-out assault on the home islands, which would have resulted in enormous casualties for the American forces.

The decision to attack the Marianas–reached at the highest levels of American command–was based on the belief that the shortest route to the conquest of the Japanese was through the Central Pacific rather than the Philippine Islands, as had been advocated by General Douglas MacArthur. The attack on Saipan was set for June 15, 1944. The companion islands of Guam and Tinian would be assaulted shortly thereafter.

Three divisions were assigned to the attack. The 2nd Marine Division, which included a number of veterans of the fighting on Guadalcanal; the 4th Marine Division, which had participated in the invasion of the Marshall Islands; and the Army’s 27th Infantry Division, under the command of Maj. Gen. Ralph C. Smith. Overall command of the amphibious landing was the responsibility of Marine Lt. Gen. Holland M. Howlin’ Mad Smith.

The 27th was a New York National Guard division that had been federalized in October 1940. In February 1942, it had been sent to the Hawaiian Islands to guard against possible Japanese attacks following the bombing of Pearl Harbor. The 27th was the first infantry division to leave the continental United States after Pearl Harbor. Ralph C. Smith was promoted to major general on November 20, 1942, and was placed in command of the 27th.

At the time of the Saipan invasion, the 27th Division consisted of three infantry regiments: the 105th Regiment from the Troy-Cohoes area of upstate New York (originally the 2nd New York Regiment, which fought with distinction during the Spanish-American War and World War I); the 106th Infantry Regiment from the Albany-Schenectady-Utica area (formerly the 10th New York Infantry, which also served in the Spanish-American War); and the 165th Infantry Regiment (formerly the 69th New York Infantry of Civil War and World War I fame) from the New York City area.

The invasion force was made up of 535 ships carrying more than 127,000 troops. Naval bombardment began on June 11, 1944, and lasted for more than three days. The Navy bombarded both coasts in order to confuse the Japanese as to the true site of the landings. The landings commenced on June 15, 1944, with the 2nd Marine Division hitting the Red and Green beaches north of Afetna Point and the 4th Marine Division landing on the Blue and Yellow beaches near the village of Charan Kanoa on the west side of the island. The 27th Division remained on board ship as a floating reserve.

Saipan had been occupied by the Japanese since World War I and had been colonized in the 1920s and 1930s. At the time of the American invasion, there were about 30,000 civilians on the island, together with about 26,000 army troops of the Japanese 43rd Division and 6,000 naval personnel. The military commander of the island was Lt. Gen. Yoshitsugu Saito.

After landing on June 15, the Marines met with fierce Japanese resistance. By the end of the day, the Marines had suffered more than 2,000 casualties. On the morning of June 16, the Japanese launched a strong counterattack against the 4th Marine Division in the Yellow Beach area just south of Charan Kanoa. They put a large number of civilians, including women and children, at the front of the attacking forces to create the impression that a surrender was taking place. The Marines were frustrated by having to hold their fire, but once they discovered the ruse they quickly annihilated the attackers.

When Admiral Raymond A. Spruance, commander of the Fifth Fleet and overall commander of the Saipan invasion, learned that the Japanese fleet was approaching the Marianas, he decided to place the 27th Division on shore to free up his fleet for the impending naval battle. Admiral Spruance subsequently led his naval forces to victory at the Battle of the Philippine Sea.

At dusk on June 16, elements of the 27th began to disembark. Two battalions of the 165th Infantry landed on Blue Beach and established contact with the 4th Marine Division. Early on June 17, the 105th Infantry landed near Agingan Point on the extreme southwest coast of the island and moved to support the 165th Infantry in an attack on Aslito airfield. By 10 a.m. on June 18, Aslito had been captured. The 105th then moved to the eastern end of the airfield, where the men dug in for the night.

Early in the morning of June 19, the 1st Battalion of the 105th resumed the attack eastward toward Nafutan Point. The battalion was led by Colonel O’Brien, described by the division historian as a cocky little rooster of a man who couldn’t stand still.

At Ridge 300, the 1st Battalion ran into heavy Japanese machine-gun fire. Colonel O’Brien obtained permission to shift the attack from the west to the north of Ridge 300 so that he would be able to utilize American tank support and perhaps outflank the Japanese on the ridge. Late in the afternoon of June 19, the 1st Battalion, supported by tanks, began its attack, but it bogged down and Colonel O’Brien decided to have his men dig in for the night.

Sergeant Thomas Baker of Company A, 1st Battalion, moved out of his position toward the ridge and observed the location of several of the enemy’s positions. He borrowed a bazooka from one of his comrades and, under heavy enemy fire, walked into the field, calmly knelt down and fired his weapon into an enemy gun position, knocking it out with his second round. He then walked back to his company with Japanese bullets flying all around him.

At about noon on June 20, the 1st Battalion moved south and west of Ridge 300 toward Nafutan Point, with the goal of outflanking it the next day. That night there was a lot of enemy activity along the 1st Battalion’s front. One Japanese soldier ran in front of Company A, shouting, Shoot me! Shoot me! at the top of his lungs. It was a ruse to get the Americans to reveal their positions, a ruse that did not work.

On June 21, three tanks supporting the advance of the 1st Battalion were hit by intense enemy fire as they approached the Japanese position on the ridge. The tanks were forced to button up; they then began firing on Companies A and C by mistake. Colonel O’Brien, who was on the line with the fighting troops, tried frantically to reach the lead tank by radio but was unable to make contact. He ran through heavy enemy fire to the lead tank, mounted it and banged on the turret with his .45-caliber pistol until he got the driver’s attention. He then ordered the tank to change direction and attack the enemy’s position.

O’Brien remained on top of the tank throughout the engagement, fully exposed to enemy fire. When the battle was over, he crawled down from the tank, holstered his .45 and picked up a wounded infantryman, who he then carried to the rear for medical treatment.

The second phase of the Saipan battle began on June 21, when General Howlin’ Mad Smith ordered the 27th Division to turn northward and attack up the center of the island, supported by the 2nd and 4th Marine divisions, which were given the responsibility of attacking up the coastlines and isolating the Japanese defenders in the northern portion of the island.

The 2nd Battalion of the 105th was assigned to mop up the Japanese still on Nafutan Point. The other two battalions of the 105th went north with the balance of the division. Smith had given the 2nd Battalion an impossible task. It had to cover a front of almost 3,000 yards with a force of fewer than 600 men against a Japanese force of almost 1,200. Inevitably, the Japanese broke through the 2nd Battalion’s position on June 27, but they were annihilated by the 3rd Battalion of the 105th, plus Marine units that were then in the vicinity of Aslito airfield. Nafutan Point was declared secure on June 27.

In the meantime, on June 23, the rest of the 27th Division had attacked north through what became known as Death Valley. The nightmarish terrain between Mount Tapotchau and what American soldiers had dubbed Purple Heart Ridge featured sheer cliffs and hills. The valley itself was a plateau of open farmland about three quarters of a mile wide. The Japanese had hidden in the caves along the cliffs. Units of the 27th moving through the valley, including the 106th Infantry Regiment, which had just rejoined the division, were subject to intense enemy fire. The soldiers had to advance through wooded areas at the opening of a plateau onto a flat plain where the Japanese held the high ground on both sides.

The enemy had carefully prepared artillery, mortar and machine-gun positions on the cliffs, which controlled the entire area. One observer compared the Americans’ situation to that of the British Light Brigade, which charged the Russians at Balaclava.The 2nd and 4th Marine divisions moved up the coasts of the island with little or no opposition. The 27th Division’s progress through Death Valley was slowed by the difficult terrain as well as the Japanese opposition.

Claiming that the 27th Division was not advancing fast enough, on June 24 Smith decided to relieve the commander of the 27th Division, Maj. Gen. Ralph C. Smith. Ostensibly, the leader of the 27th Division was relieved of his command because he had contravened an order regarding the disposition of troops at Nafutan Point, and the 27th had failed to make a coordinated attack on June 23, which had jeopardized the Marine troops attacking up the coasts. Ralph Smith was replaced by Maj. Gen. Sanderford Jarman. The incident triggered a rivalry between the Army and Marine Corps that has never been satisfactorily resolved.

On June 26, two battalions of the 165th Infantry, along with the 1st Battalion of the 105th Infantry, joined the 4th Marine Division in an attack toward the villages of Donnay and Hashigoru on the east side of the island. The attack met with heavy Japanese opposition.

On June 27, the advance continued, but the soldiers ran into heavy Japanese gunfire from a high ridge above Donnay. The next day, Colonel O’Brien decided to flank the Japanese position on the ridge rather than assault it frontally. He organized a large patrol to work its way around to the rear of the enemy position.

When the patrol action stalled, O’Brien left his covered position and ran across a field exposed to enemy fire, armed only with a pistol, to reach his troops. He took charge of the patrol and led his men into a vicious firefight with the Japanese. Led by O’Brien, the men burst into a small canyon, taking the enemy completely by surprise.

Within 10 minutes, the soldiers of the 105th had captured a 77mm fieldpiece and five machine guns, and had killed or routed all the Japanese in the ridge position. By nightfall, all of Obie’s Ridge, as it came to be called, was in American hands. The 1st Battalion held the position through the night and the next day against numerous Japanese counterattacks.

June 30 was the beginning of the end of the Saipan battle. The Japanese were observed moving north toward Marpi Point, and it was clear that this was to be their last stand. On July 1, the 4th Marine Division moved north and east toward Marpi Point, the 2nd Marine Division moved up the west coast toward Tanapag, and the 27th Division continued its attack up the center of the island.

The morning of July 2 was dark and rainy. O’Brien’s battalion had been ordered to close up behind the 3rd Battalion of the 105th, now positioned near Charan Danshii, in the center of the island. The position was a proverbial hornet’s nest, exposed to heavy Japanese fire from guns along the hillside.

The 1st Battalion was to move through the 3rd Battalion until it hooked up with the left flank of the 165th Infantry and the right flank of the 106th Infantry. The movement was hazardous because it required an advance in daylight across 1,700 yards of open ground. Since the area had not yet been cleared of Japanese forces, there was a very real chance that the soldiers of the 1st Battalion of the 105th could dig in for the night and find the Japanese both in front of them and behind them.

At 2:40 p.m. on July 2, O’Brien ordered his troops to march double time in order to reduce their exposure to enemy fire. The battalion reached its objective on schedule and dug in on the left flank of the 165th for the night. Sergeant Baker of Company A, recognizing that the Japanese might attack from the rear, volunteered to go back and eliminate as many of the enemy as possible. He and three other soldiers from the 105th killed 18 Japanese troops in the space of an hour. At one point, Baker walked directly into a concrete pillbox and killed four Japanese soldiers with one burst of fire before they could get off a shot.

On July 3, Garapan, on the west coast of Saipan, was captured by the 2nd Marine Division, and the 27th Division continued its movement north toward Tanapag Harbor.

By late afternoon on July 4, the 105th had secured Flores Point and had pushed forward up the beach. The 2nd Battalion of the 105th, which had been at Nafutan Point, then rejoined the regiment. O’Brien’s battalion moved past Hara-Kiri Gulch (so named because a number of Japanese in caves along the cliffs had killed themselves by detonating grenades) and advanced along the beach until they were about 1,200 yards south of Makunshka.

O’Brien’s orders were explicit. Keep going, he said. No matter what else happens, keep going. In spite of intense enemy fire, the advance proceeded rapidly. By dark on July 6, the 1st Battalion was dug in on the east side of a railroad track that ran north-south about 150 yards west of the beach near the Tanapag plain.

The 2nd Battalion of the 105th was dug in on the west side of the railroad track, but there was a gap between the 1st and 2nd battalions’ positions. O’Brien immediately recognized the problem and requested reinforcements. When he was told none were available, he ordered all his anti-tank weapons moved into position to cover the gap. He also placed the battalion’s heavy machine guns in position to protect the perimeter against a possible Japanese attack.

On the evening of July 6, the 1st and 2nd battalions of the 105th were dug in about 2,000 yards north of the regimental command post, roughly 1,400 yards south of Makunshka. Later that evening, the Japanese began probing the perimeter looking for a weak spot. The perimeter attacks continued all night. At about 4:45 a.m. on July 7, the Japanese launched the gyokusai attack. (Gyokusai can be roughly translated as breaking the jewel, a reference to the destruction of an entire Japanese unit. Such large-scale suicide attacks were made only at the behest of Imperial General Headquarters.) The exact number of attackers will never be known, but it is estimated that more than 4,000 Japanese participated in this last-ditch assault on the American forces near Makunshka.

The Japanese had begun to assemble for the attack shortly after dark on July 6. All wounded soldiers who were not able to walk and bear arms were killed under the orders of the Japanese commanders. The Japanese commanders themselves then committed suicide. Every man able to walk was armed with whatever weapons were available. There were not enough rifles to go around, so some of the men carried sticks, rocks or whatever they could find.

The attackers came on like madmen, drunk on sake and beer. They were led by about 200 officers waving swords and yelling at the top of their lungs. In front of the charging masses a half-dozen men held aloft a large red flag, like the vanguard in a dramatic pageant. Behind them came the fighting troops and, most incredible of all, hundreds of limping and hobbling men with bandaged heads, on crutches and scarcely armed.

Major Edward McCarthy, then in command of the 2nd Battalion of the 105th and one of the few officers of the regiment to survive the attack, described the scene as follows: It reminded me of one of those old cattle-stampede scenes of the movies. The camera is in a hole in the ground and you see the herd coming and they leap up and over you and are gone. Only the Japs just kept coming and coming. I didn’t think they’d ever stop.

The Japanese troops swept down the narrow tracks of the railroad, which skirted the beach, and smashed into the dug-in soldiers of the 105th with a vengeance. The Americans fought well and with tenacity, their weapons positioned so that the Japanese had to climb over their own dead in order to get at them.

Still the Japanese soldiers came on, overrunning the two battalions of the 105th as well as the 10th Marine Artillery battery, which had been placed in the rear of the 105th Regiment’s position. The Marines fought hard, but they were outnumbered and were forced to abandon their fieldpieces to the enemy. The following day a number of Marines were found on the field, killed in hand-to-hand combat.

The fighting was furious. O’Brien, who was idolized by his men, took the lead in opposing the Japanese attack. Left-handed, he always carried a pistol in a shoulder holster under his right armpit. According to the division historian, O’Brien was without doubt responsible for the great stand made by the men of his battalion when the Japanese first hit the perimeter. He stood his ground with a pistol in each hand, encouraging his men to hold off the enemy. He was seriously wounded in the shoulder but refused to be evacuated.

O’Brien ran up and down the line, exhorting his troops to hold. When the Japanese broke through, he grabbed a rifle from a wounded man in a foxhole and fired on the enemy until he was out of ammunition. He then manned a .50-caliber machine gun on an abandoned jeep, firing on the Japanese until once again he ran out of ammunition. When last seen alive, O’Brien was surrounded by saber-wielding Japanese officers and the bodies of the Japanese he had killed. At least 30 dead Japanese soldiers were found near his body.

An eyewitness to the battle, Sergeant John G. Breen of Company A, 1st Battalion, 105th Infantry, stated that Obie was one of the boys that day. He died right on the front line with us. His last words–heard over the shrieks of the charging Japanese, the cries of his wounded soldiers and the deafening gunfire–were, Don’t give them a damned inch.

Sergeant Baker was also a hero in that battle. Although seriously wounded, he refused to be removed from the battlefield and insisted that he be left to die rather than risk the lives of his buddies. He asked to be placed in a sitting position against a small telephone pole and was given a cigarette and a fully loaded pistol. Two days later, Baker’s body was found in exactly that position with eight enemy soldiers dead in front of him.

The Battle of Saipan was a devastating defeat for the Japanese. More than 30,000 Japanese soldiers died, along with an untold number of civilians, many of whom committed suicide by jumping off the cliffs near Marpi Point. In front of the 105th’s positions on the Tanapag plain were 2,295 dead Japanese. Another 2,016 bodies lay in the rear of the 105th’s position, for a total of 4,311 Japanese killed in the attack on the beaches at Tanapag.

American casualties were also heavy. The 1st and 2nd battalions of the 105th were virtually wiped out. In slightly more than 12 hours of fighting, those units sustained losses of 406 killed and 512 wounded. In the 1st Battalion, only one officer, Lieutenant John Mulhearn of Company B, emerged unscathed. Major McCarthy of the 2nd Battalion survived, but all his staff and company commanders were either killed or wounded.

Total casualties for the Marines and soldiers who fought on Saipan amounted to 786 officers and 13,438 enlisted men killed, wounded or missing in action.

This article was written by Francis A. O’Brie and originally appeared in the May 1997 issue of World War II magazine.

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