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100th Infantry Battalion
100th infantry battalion.jpg
Active 4 June 1942 – 6 August 1946
31 July 1947 – Present
Allegiance United States of America
Branch United States Army
Type Separate infantry battalion
Garrison/HQ Fort Shafter
Nickname(s) Purple Heart Battalion
Motto(s) Remember Pearl Harbor
Colors Blue and White
Engagements World War II
Iraq War[1]
Decorations Presidential Unit Citation (Army) (4)
Meritorious Unit Commendation (Army)
LTC Daniel J Austin
Command Sergeant Major CSM Beau A Tatsumura

The 100th Infantry Battalion (Japanese language: 第100歩兵大隊 ) was a unit within the U. S. Army's 34th Infantry Division during World War II. The primarily Nisei battalion was composed largely of former members of the Hawaii Army National Guard. Upon its activation, the 100th saw heavy combat during World War II before and after combining with the 442nd Infantry Regiment, another mostly Nisei military unit, into a single fighting combat team. The 100th exists today as the only remaining combat arms unit in the United States Army Reserve, the other units all being combat support or combat service support.[2] Based at Fort Shafter, Honolulu, Hawaii, the 100th Battalion has reservists from Hawaii, American Samoa, Guam and Saipan, and has been activated and deployed to Iraq and Kuwait. Historically, the unit is referred to as the "Purple Heart Battalion", with the motto "Remember Pearl Harbor".

Prior to the 100th Battalion[]

On the morning 7 December 1941, the United States was attacked by the Empire of Japan, marking the beginning of World War II for the United States. After the attack, Japanese-Americans and those of Japanese descent would not only be fighting the enemy across the Pacific but also fighting prejudice at home as well. Chaos ensued in the hours that followed the Pearl Harbor attack, but those who were a part of the 298th and 299th Hawaii National Guard knew clearly what they had to do: prepare for an invasion, guard Hawaiian shores, clear the rubble, donate their blood, and aid the wounded.[3] Although their patriotism to the U. S. was clearly defined as they prepared the beaches against a Japanese invasion, the color of their skin and Japanese ancestry could not prevent the coming storm. Three days after the attack, their rifles were stripped from them because of the way they looked; they were thought to be spies or secret soldiers of Japan, but eventually those rifles were returned to them.[3] Nearly the same situation happened with those Nisei that were a part of the ROTC program at the University of Hawaii; they were discharged from the Hawaii Territorial Guard because of the way they looked. Those former members would eventually make their own stand as they formed the Varsity Victory Volunteers.

The reason for such prejudice was because at 11:30 a.m. Martial Law was declared and the governor at the time, Joseph Poindexter, told President Franklin D. Roosevelt that his greatest fear was sabotage by the large Japanese population in Hawaii. This provoked the FBI rounding up known Japanese sympathizers, Buddhist priests, language school principals and teachers, civic and business leaders, fisherman, and instructors of judo and related martial arts. The War Department discharged all soldiers of Japanese ancestry, had all Japanese-Americans on the west coast rounded up and placed in internment camps around the U. S., deactivated of the Hawaii Territorial Guard, and had all Japanese-Americans reclassified as 4-C: enemy aliens.[4]

History says General Delos Emmons, appointed military governor on 17 December, was for placing Japanese-Americans in internment camps and having them reclassified as enemy aliens, but in actuality he wanted to give them a chance to prove their patriotism. After General Emmons agreed to let the Varsity Victory Volunteers form, a confidential memo was sent to the War Department in early April 1942 stating that there were 2,000 Japanese-American soldiers now serving and many more who wished to serve to demonstrate their loyalty to the United States. Their desire was to organize into a fighting force to be sent to Europe or Africa to fight the Germans and Italians; that request was later denied by the War Department.[5]

Formation of the 100th Battalion[]

Nisei that were in the Hawaii National Guard continued their duties as normal but by June things had begun take turn that would give those of Japanese ancestry the chance to prove everyone wrong and to show their true loyalty to the United States. The Battle of Midway was well underway by 4 June 1942 but as this decisive battle was happening, 1,432 Nisei of the Hawaii National Guard had their weapons taken away and boarded onto the Matson liner SS Maui under the cover of night and shipped to the mainland without saying goodbye to their family or loved ones. Under the title "Hawaiian Provisional Infantry Battalion" the week long zig-zag journey finally took them to a port in Oakland where the 1,432 Nisei would finally be known as the 100th Infantry Battalion on 12 June 1942.[6] The unit number was an indication of the Army's recently formulated plan for a modern organization for the Combat Arms. Under normal pre-war Army procedures, all Infantry battalions were organic to the Regiment they were a part of, and were known as, for instance, "1st Battalion, 5th Regiment." With the new system of organization, the Infantry Regiment was reorganized as a Headquarters with no Organic battalions, but with three Separate Battalions attached. The Headquarters was organized into three Combat Commands that could be dispatched on separate combat actions with units that were attached. One Infantry Battalion would be assigned to a Combat Command, with attachments from the higher headquarters reserve. The 100th was not attached to any other military organization but its own fighting unit and would come to be known as the "One-Puka-Puka" (Puka means "hole" in Hawaiian).

Camp McCoy and Camp Shelby[]

100th Infantry soldiers receiving training in the use of grenades in 1943.

Following their arrival at Oakland, the 100th boarded a train that would take them to their final destination, Camp McCoy, Wisconsin. Immediately following their arrival to Camp McCoy many of the Nisei could feel the animosity in the air; they faced prejudice, suspicion, and distrust from fellow soldiers and highly placed military and political leaders.[7] Upon arrival, men of the 100th were immediately marched off the train and into tents, four soldiers per tent, which contained a bunk bed, blanket, towels, and backpack. It would be several months until the Nisei would be properly placed into military barracks. As time progressed soldiers were permanently placed into military units, such as Companies A through E, and pushed through intense and rigorous training: building physical stamina, improving marksmanship, and learning military tactics.[8]

While in training at Camp McCoy, the Nisei soldiers knew there was prejudice in the air but were unaware of how deep it was in higher command. Some of the white officers and NCO's appointed to the 100th were schooled in psychology and were ordered to test their physical and military capabilities but most of all their loyalty.[7] The military's attempt to winkle out loyalists to the Japanese Empire was a complete failure. The 100th dominated their training and took to heart everything they did. Competition was desired by every Nisei as they competed with other companies in marksmanship, baseball, softball, physical combat such as scuffles, boxing, and wrestling.[9]

On one such occasion that happened to prove the loyalty and bravery of the new recruits, five Nisei soldiers received the Soldier's Medal for their heroism in rescuing several local civilians who almost drowned on a frozen Wisconsin lake.[10]

Even though the Nisei were able to prove that they were just as an American as any other soldier, they were still scrutinized as being different, something less than human. One disturbing occasion proved that. About 25 of the Japanese American soldiers were sent to a secret training mission on a small island, Cat Island, near the mouth of the Mississippi River . Some top military officers thought that the "Jap" soldiers smelled differently, and that the Nisei soldiers would give off a similar scent. So for three months these 25 Nisei were ordered to train attack dogs to "smell Japs." Of course the training didn't work.[3]

Training at Camp McCoy would last for six months until on 6 January 1943 the 100th Battalion was transferred to Camp Shelby, Mississippi. The 100th was attached to the 85th Division under Major General Wade Haislip and would receive even tougher training than they did at Camp McCoy. Upon arrival at Camp Shelby the 100th received the same amount of skepticism as they did at McCoy and were thought to not be able to pass the tasks at hand but 100th were able to prove them wrong as they passed the training exercises with flying colors gaining the respect of their superiors; even when fighting the weather, chiggers, ticks, dry land snakes, reptiles, and cotton-mouth water moccasins.[11] It would be at Camp Shelby where 100th would receive its most intense and advanced training and then eventually sent to Camp Clairborne, Louisiana for field exercises and war games that would ready them for combat.[12]

On return from Camp Clairborne, the 100th had finally met up with the newly formed 442nd Regimental Combat Team on 16 July and advised them of Army life and ways and on 20 July 1943 the 100th received its battalion colors and motto, "Remember Pearl Harbor," as requested by the unit.[13]

Africa and Italy[]

After training at Camp McCoy, Wisconsin, and Camp Shelby, Mississippi, the battalion was ready to deploy, but was refused by General Dwight D. Eisenhower. General Mark Clark, commanding the Fifth Army, accepted the offer, and the 100th deployed from Shelby on 11 August by train to Camp Kilmer, New Jersey and then to the Mediterranean on 20 August 1943.

The 100th arrived in Oran, North Africa on 2 September 1943 and became a part of the 133rd Regiment under the 34th Division and took part in training with Caucasian soldiers. Things began to look up for the 100th as they were finally getting the chance to prove themselves that they were just as American as any other white civilian or soldier. On 19 September the 34th Division sailed from Africa to southeast of Naples, with the 100th with them.

The unit entered combat on 29 September 1943, near Salerno in Southern Italy. The unit fought well as they advanced 15 miles in 24 hours for a week against strong enemy resistance and taking on casualties allowing them to gain their first major victory by taking Benevento, an important rail center and road intersection.[14] The 100th even had to cross the twisting, wet, and muddy Volturno River three times taking on heavy German machine gun fire and rocket launchers before driving the German force even further north.[14] But this would end up being a walk in the park compared to their next objective. The Nisei soldiers had gained respect from their fellow soldiers but also the enemy as well and in turn gained respect for the German fighting force. However, the deciding factor of who was the more superior fighting force and demanded the most respect would take place at the Gustav Line at Monte Cassino.

Monte Cassino[]

"When you read that a town was taken, or a certain hill was taken, remember that in the process of that accomplishment lives of fine fellows were lost, and also, that during this accomplishment for the participants, life was a horrifying massacre. You lose your buddies-fellows with whom you laughed, ate, slept, sweated. They grow to be more than mere buddies. They become blood relations to you and they die before your eyes-not a pleasant, natural death, but an unimaginable kind of mutilation mixed with groans and prayers ending with a gurgling last breath. Only five minutes ago you might have been laughing with that buddy of yours."

This was the situation at the Gustav Line as the 100th received its most intense fight yet as they fought from mountain to mountain. At the top of Monte Cassino stood a grand but old monastery, this was the grand prize for the 5th Army. It would be the key taking in order to finally snag Rome from the grips of the Nazis. To take the Gustav Line, the Allies would have to descend into the Rapido River valley, traverse two miles of open fields filled with landmines, mud, and knee-deep cold water, cross a swift-moving river, then climb past more mines and barbed wire and up the steep, rocky slopes, to the 1500-foot peak of Monte Cassino. From there they would have to ascend still higher to a four-story fortress, with 10-foot-thick stone walls. This was the St. Benedictine monastery.[16] The battle had commenced in January and long struggle for the 100th would begin. It would be here where they would earn their nickname the "Purple Heart Battalion." Under the cover of night A and C companies passed their way through the river reaching the wall where the enemy was located and held their ground under intense fire into the next day. B company was not so lucky as A and C were for they were met with heavy machine gun fire as their cover by the smoke screen was blown away leaving only 14 of the original 187 men in B company to reach the wall.[16]

"During the first daylight hours our battalion observation post started with 26 individuals including the artillery liaison team communication people and the intelligence section. By nightfall only four of us were left. Major Clough, our Battalion Commander, and myself (Captain Kim) in one location and Pfc Ginger Minami and Private Irving Akahoshi in another location, 20 yards away. Everyone else was either dead or wounded. Major Clough was ordered by Colonel Marshall, 133rd Regiment Commander, to commit "B" Company across the open flats at daybreak. Jim protested that this was a suicide mission. Lieutenant Colonel Moses, the 1st Battalion Commander, to our right, had orders to also commit his reserve company. He protested and said he would personally lead his company because he could not issue such an order without sharing their danger. However, if he survived, he would prefer court martial charges against Colonel Marshall."

Captain Young-Oak Kim, a Korean-American from Los Angeles who served in the unit from 1943 to 1944.[17]

The three companies were immediately pulled back to San Micheli the next night. Following their pull from the front lines the 100th was ordered to take Castle Hill in which they did on 8 February. The hill was held for four days dealing with not only machine gun fire but tanks as well. The hill was a key location for it was close to the monastery but the 34th division's right and left flanks were unable to hold their positions because of heavy German resistance. The 100th was again ordered back.[14]

The order came from high command to bomb the abbey in order to lighten the resistance. The bombing continued for three days and when it finally finished the second assault commenced. The bombing didn't lighten up a single bit as one platoon of the 100th received very heavy casualties as only five of forty soldiers survived.[18] Badly beaten the 100th again was pulled back into reserve and replaced by British and Indian soldiers after nearly taking Cassino. It would be these replacements who would witness first hand of what the Nisei had been through and praised them for their efforts. War correspondents would end up calling these men "little men of iron" and the "purple heart battalion."[14] This would be the last time Nisei of the 100th would see combat at Monte Cassino as they were taken back to San Michele to rest and reorganize. It would be here where replacements from the 442nd would come in to replenish the 100th's ranks.

The battle would eventually take the lives of over 50,000 allied soldiers and nearly 800 wounded and KIA of the 100th taking their numbers from 1300 strong 5 months prior to nearly 500. It wouldn't be until 17 May when Cassino would fall to the allies taking five divisions to bring it down. This would be the final campaign in which the 100th would fight with only its original soldiers because following the battle of Cassino the 100th began to receive replacements from the 442nd. It is argued that the reason there were such heavy losses was because of members of the U.S. War Department neglecting the Italian campaign by taking men and supplies away and putting it towards the coming invasion of Normandy. The battle was so horrific that it is compared to the Battle of Verdun in World War I and the Battle of Stalingrad of World War II.[19] The battalion would eventually be awarded the Distinguished Unit Citation (DUC) [later redesignated the Presidential Unit Citation (PUC)] for its actions on 26–27 June.

Anzio, Rome, and the 442[]

Following Monte Cassino, the 100th received rest from its efforts in battle in would[Clarification needed] receive two waves of reinforcements from the 442nd but the rest soon ended as they were deployed at the Anzio beachhead on 26 March 1944. The allies held a beachhead that spanned 15 miles (24 km) inland going a few miles inland[Clarification needed] and was held strong for it was a stalemate between the Germans and the Allies. The battlefield at Anzio was very similar to battlefields in World War I as there was a large stretch of land between both opposing forces declared as "No Man's Land" and both sides didn't go on a large-scale offensive. It was a stalemate between the two as both sides only did battle at night. During the day, soldiers slept. It would take the fall of Monte Cassino to finally end the stalemate that lasted until 17 May 1944. It was decided that 23 May would be the "breakout day" for the allies as they would take to the offensive and drive the Germans north but there was a problem; there was no idea of kind of opposition they would face. During the stalemate at Anzio, not a single prisoner was taken, that is until the 100th was ordered to do so. Lieutenant Young-Oak Kim, a Korean American born in Los Angeles, California, and Nisei PFC Irving Akahoshi from the 100th volunteered to get the job done. After a two-hour and quarter of a mile crawl, two German soldiers awoke to the taste of metal in their mouths from the barrel of a gun and eventually made the crawl back to the Allied lines.[20] After gaining the information they needed, it was time to push forward to Rome. Stronghold after stronghold fell to the Allies and it was Lanuvio, the final German stronghold, that fell to the 100th Infantry Battalion.

"We had been sitting and living in foxholes at Anzio some 63 days. Then the big push out and the capture of Rome. They (100th Battalion) wiped out the last heavy German resistance we met some 12 miles south of Rome and then it was practically a walk into the city."[19]

Rome was in the grasp of the 100th but instead of walking into Rome as heroes, they were ordered to stay at the roadside on 4, 10 June kilometers[Clarification needed] from Rome and watched other troops march on by.[14] They never saw Rome. Instead, the 100th was taken 40 miles (64 km) northwest of Rome to Civitavecchia and met up with the battle-eager 442nd Regimental Combat Team. On 11 June 1944, the 100th was attached to the newly arrived 442nd but because of their exemplary efforts during the war and the long and hard-fought battles they were a part of, they were allowed to keep their original designation, giving the newly formed all-Nisei fighting unit the name 100th/442nd Regimental Combat Team under the 34th Division.[21] The 100th's story as a single unit may have ended but the 100th's story still continued through the journey of the 442nd and the battles they would end up fighting.

Monument to the Men of the 100th Battalion, 442nd Regimental Combat Team, Rohwer Memorial Cemetery


Obama with surviving veterans of the 100th after signing S.1055, a bill to grant the unit the Congressional Gold Medal

The nation's highest award for combat valor, the Medal of Honor, was conferred upon twenty-one members of the 100th Infantry battalion of the 442nd Regimental Combat Team of World War II. On 5 October 2010, the Congressional Gold Medal was awarded to the 442nd Regimental Combat Team and the 100th Infantry Battalion, as well as the 6,000 Japanese Americans who served in the Military Intelligence Service during the war.[22]

Lineage following World War II[]

  • Inactivated 15 August 1946 at Honolulu, Hawaii
  • Allotted 27 March 1947 to the Organized Reserves
  • Activated 31 July 1947 with Headquarters at Fort DeRussy, Hawaii
  • Organized Reserves redesignated 25 March 1948 as the Organized Reserve Corps;
  • Organized Reserve Corps redesignated 9 July 1952 as the Army Reserve
  • Reorganized and redesignated 29 May 1959 as the 100th Battle Group, 442d Infantry
  • Reorganized and redesignated 1 May 1964 as the 100th Battalion, 442d Infantry
  • Ordered into active military service 13 May 1968 at Fort DeRussy, Hawaii;
  • Released from active military service 12 December 1969 and reverted to reserve status
  • Location of Headquarters changed 1 September 1994 to Fort Shafter, Hawaii
  • Ordered into active military service 16 August 2004 at Fort Shafter, Hawaii
  • Redesignated 1 October 2005 as the 100th Battalion, 442d Infantry Regiment
  • Released from active military service 13 March 2006 and reverted to reserve status

Campaign participation credit[]

  • World War II:
    • Naples-Foggia;
    • Anzio;
    • Rome-Arno;
    • North Apennines;
    • Rhineland;
    • Po Valley
  • War on Terrorism:
    • Iraq


See also[]


  2. Helmly, James R. (October 2006). "Changing to a 21st–century Army Reserve". United States Army. p. 108. 
  3. 3.0 3.1 3.2 Go For Broke National Education Center – Preserving the Legacy of the Japanese American Veterans of World War II
  4. Tamashiro, Ben. Remembrances: 100th Infantry Battalion 50th Anniversary Celebration 1942–1992. Published and distributed by 100th Infantry Battalion Publication Committee. Pg. 49.
  5. Tamashiro, Ben. Remembrances: 100th Infantry Battalion 50th Anniversary Celebration 1942–1992. Published and distributed by 100th Infantry Battalion Publication Committee. Pages. 51, 53.
  6. Crost, Lyn. Honor by Fire: Japanese Americans at War in Europe and the Pacific. Novato: Presidio Press, 1994. Pg. 15.
  7. 7.0 7.1 Sterner, C. Douglas. Go For Broke. Clearfield: American Legacy Historical Press, 2008. Pg. 16.
  8. Tamashiro, Ben. Remembrances: 100th Infantry Battalion 50th Anniversary Celebration 1942–1992. Published and distributed by 100th Infantry Battalion Publication Committee. Pg. 71.
  9. Tamashiro, Ben. Remembrances: 100th Infantry Battalion 50th Anniversary Celebration 1942–1992. Published and distributed by 100th Infantry Battalion Publication Committee. Pg. 73.
  10. Sterner, C. Douglas. Go For Broke. Clearfield: American Legacy Historical Press, 2008. Pg. 17.
  11. Tamashiro, Ben. Remembrances: 100th Infantry Battalion 50th Anniversary Celebration 1942–1992. Published and distributed by 100th Infantry Battalion Publication Committee. Pgs. 77 and 79.
  12. Sterner, C. Douglas. Go For Broke. Clearfield: American Legacy Historical Press, 2008. Pgs. 20–21.
  13. Tamashiro, Ben. Remembrances: 100th Infantry Battalion 50th Anniversary Celebration 1942–1992. Published and distributed by 100th Infantry Battalion Publication Committee. Pg. 83.
  14. 14.0 14.1 14.2 14.3 14.4 "Go For Broke National Education Center - Preserving the Legacy of the Japanese American Veterans of World War II". Retrieved 2012-08-17. 
  15. Sterner, C. Douglas. Go For Broke. Clearfield: American Legacy Historical Press, 2008. Pg. 24.
  16. 16.0 16.1 "Go For Broke National Education Center - Preserving the Legacy of the Japanese American Veterans of World War II". Retrieved 2012-08-17. 
  17. Crost, Lyn. Honor by Fire: Japanese Americans at War in Europe and the Pacific. Novata: Presidio Press, 1994. Pgs. 106 and 107
  18. Sterner, C. Douglas. Go For Broke. Clearfield: American Legacy Historical Press, 2008. Pg. 29.
  19. 19.0 19.1 Crost, Lyn. Honor by Fire: Japanese Americans at War in Europe and the Pacific. Novata: Presidio Press, 1994. Pg. 97.
  20. Sterner, C. Douglas. Go For Broke. Clearfield: American Legacy Historical Press, 2008. Pgs. 34 and 35.
  21. Crost, Lyn. Honor by Fire: Japanese Americans at War in Europe and the Pacific. Novata: Presidio Press, 1994. Pg. 147.
  22. Steffen, Jordan (6 October 2010). "White House honors Japanese American WWII veterans". Archived from the original on 10 October 2010.,0,7017069.story. Retrieved 9 October 2010. 


Moulin, Pierre. U.S. Samurais in Bruyeres, U.S. Army Museum of Hawaii. ISBN 978-2-9599984-0-9

External links[]

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