509th Infantry Regiment (United States)
This article needs additional citations for verification. (May 2008) (Learn how and when to remove this template message)
The 509th Infantry Regiment (previously the 509th Parachute Infantry Regiment) is an airborne infantry regiment of the United States Army. The unit was initially activated as a single battalion, the 504th Parachute Infantry Battalion, in October 1941 at Fort Benning, Georgia. Nicknamed "Geronimo", the 509th conducted the U.S. Army's first combat jump during World War II on 8 November 1942, flying 1,500 miles from England to seize Tafarquay airport in Oran, Algeria. The 509th made a total of five combat jumps during the war.
|509th Parachute Infantry Regiment|
509th Infantry Regiment
509th Infantry Regiment coat of arms
|Branch||United States Army|
|Part of||Joint Readiness Training Center;|
4th Brigade Combat Team (Airborne), 25th Infantry Division
|Garrison/HQ||Fort Polk, Louisiana|
Fort Richardson, Alaska
|Nickname(s)||The Gingerbread Men|
|Motto(s)||All the Way / Geronimo|
|Colors||Black and gold|
|Engagements||World War II|
|LTC John H. Moltz|
William P. Yarborough
|Distinctive unit insignia|
|Unit beret flashes for 1st and 3rd Battalions|
U.S. Infantry Regiments
|508th Infantry Regiment||511th Infantry Regiment|
The 1st and 3rd Battalions remain active. 1st Battalion serves as the Opposing Force (OPFOR) at the U.S. Army's Joint Readiness Training Center at Fort Polk, Louisiana, while 3rd Battalion is assigned to the 4th Brigade Combat Team (Airborne), 25th Infantry Division, at Fort Richardson, Alaska. The 509th operates independently from larger airborne units such as the 82nd Airborne Division.
The advent of World War II ushered in a need for highly mobile units capable of quick insertion within the theater of battle by the Allies. Originally constituted 14 March 1941 as the 504th Parachute Infantry Battalion (PIB) and activated on 5 October 1941, the 509th PIB qualified its first paratroopers at Fort Benning, Georgia. The unit moved to Fort Bragg, North Carolina and re-designated as 2d Battalion, 503d Parachute Infantry in February 1942. The 503rd and 504th Parachute Infantry Battalions were joined together to form the 503rd Parachute Infantry Regiment on 24 February 1942 at Fort Bragg, NC. The 504th PIB was reorganized and re-designated as the 2nd Battalion, 503rd Parachute Infantry Regiment. Companies A, B, and C were re-designated as 503rd PIR, Companies D, E, and F, respectively. This unit trained with the British 1st Parachute Brigade in England, earned the honorary title "Red Devils", and were authorized to wear the maroon beret. The maroon beret remains an iconic symbol of airborne units. Paratroopers wear it today.
In June 1942, under the command of Lieutenant Colonel Edson Duncan Raff, the 2nd Battalion, 503rd PIR was detached from the 503rd PIR and sailed to Scotland, becoming the first American parachute unit to go overseas in World War II. It was attached to the British 1st Airborne Division for training, which included mass tactical jumps from C-47 aircraft at 350 feet, extensive night training, and speed marching for 10 miles to and from the training area daily; and on one occasion, marching 32 miles in 11 hours. In summer 1942, Allied forces were completing the task of planning Operation Torch, the invasion of North Africa, with the 2nd Battalion, 503rd PIR scheduled to take the lead and make the first combat jump.
Operation Torch was the first joint military action undertaken by the Allies in World War II. This was the springboard for the idea, formed by British Prime Minister Winston Churchill, of attacking the "soft underbelly of Europe" before attempting a cross-channel attack from England onto mainland Europe. The main objective of Torch was to seize French Northwest Africa and, for political reasons, the Americans would lead operation. The airborne segment of the operation entailed flying 1,500 miles from England to seize two French airfields near Oran.
On 2 November 1942, days before Operation Torch began, the unit was re-designated once again as 2d Battalion, 509th Parachute Infantry. On this momentous day, as C-47s flew over the English countryside, the 509th paratrooper was born.
World War IIEdit
North Africa Campaign - Operation TorchEdit
The 2-503rd newly named 2-509th PIR carried out the first American combat jump during the invasion of North Africa. The transport planes flew all the way from English airfields to the African coast. This first operation was unsuccessful, with 7 of its 39 C-47s widely scattered. Only 10 aircraft actually dropped their troops, while the others unloaded after 28 troop carriers, nearly out of fuel, landed on the Sebkha d'Oran, a dry lake near their target. The 509th marched overland to occupy its objective, and on 15 November 355 paratroopers successfully dropped on the Youks-les-Bains Airfield.
Liberation of Ventotene - ItalyEdit
Forty-six Paratroopers from the Scout Company 509th (the first pathfinders) participated in the liberation of Ventotene, a small Italian island, on 9 September 1943. The German commander was tricked into surrendering to the weaker American force before realizing his mistake. An account of this is given in John Steinbeck's "Once There Was a War."
Italy & Southern FranceEdit
During 1943–1944, the 509th PIR served in the Italian mainland campaign and invasion of southern France. Because of the terrain, in both campaigns the regiment often found itself serving as de facto mountain infantry.
The Italian mainland campaign began with a combat jump at Avellino, on 14 September 1943.
On 22 January 1944, the 509th PIR took part in the seaborne landings at Anzio, just south of Rome. Corporal Paul B. Huff, a member of the 509th, became the first US paratrooper to be awarded the Medal of Honor, on 29 February 1944, after an action at Anzio.
A second combat jump, on 15 August 1944, occurred around Le Muy and St Tropez in southern France.
France - Operation Dragoon - Southern FranceEdit
Belgium - Battle of the BulgeEdit
On 10 December 1943 the battalion was redesignated as the 509th Parachute Infantry Battalion.
During the Battle of the Bulge in late 1944, the 509th fought in Belgium to blunt the German attack. An account of this battle is described in the book "Bloody Clash at Sadzot." The 509th Infantry Regiment's service during World War II concluded at the end of January 1945 near St. Vith, Belgium. Of the original 700 paratroopers who entered the battle, approximately ninety-three percent were injured. Effective 1 March 1945, the 509th PIB was disbanded, and the soldiers who remained were reassigned as replacements in the U.S. 82nd Airborne Division.
Post-World War IIEdit
After World War II, the colors of the 509th remained inactive until 1963, when Company A, 509th PIB was reactivated as HHC, 1st Battalion (Airborne), 509th Infantry, and Company B, 509th PIB was reactivated as HHC, 2nd Battalion (Airborne), 509th Infantry.
Since 1958 the 8th Infantry Division in Germany had had an Airborne component consisting of the 1st Airborne Battle Group, 504th Infantry, and the 1st Airborne Battle Group, 505th Infantry, as well as other supporting elements on jump status. When the division reorganized from the Pentomic structure to the new structure using brigades and battalions, 1-504th and 1-505th were replaced by 1-509th and 2-509th, respectively. Located at Lee Barracks in Mainz-Gonsenheim, Germany, the two battalions formed the infantry component of the 1st Brigade (Airborne), 8th Infantry Division (Mechanized). Other units of the brigade included the 5th Battalion (Airborne), 81st Artillery; Troop A (Airborne), 3rd Squadron, 8th Cavalry; Company A (Airborne), 12th Engineer Battalion; and Company B (Airborne), 8th Medical Battalion.
In 1973, as the 1st Brigade's jump status was ending, a new unit with the designation of 3d Battalion (Airborne), 509th Infantry (bearing the lineage of the World War II-era Company C, 509th PIB) was activated to form an Airborne Battalion Combat Team (ABCT) from elements of the existing airborne forces within the brigade. After a brief training period at Rhine Kaserne Barracks in West Germany, the unit moved to Vicenza, Italy, as a separate Airborne Battalion Combat Team. Commanded by LTC Ward M. Lehardy, it was composed of a Headquarters and Headquarters Company (HHC), a Combat Support Company (CSC), three Airborne Rifle Companies, and Company D, a field artillery battery, the predecessor of what later became Battery D, 319th Field Artillery (towed 105mm) activated on 1 October 1988. The colors of 1-509th and 2-509th were reflagged as 2-28th and 2-87th. Shortly after its arrival in Italy, the 3d Battalion, 509th Infantry was reflagged as the 1st Battalion, 509th Infantry. In 1983, 1-509th in Italy was reflagged as the 4th Battalion (Airborne), 325th Infantry to align it with elements of the 82nd Airborne Division at Fort Bragg under an Army-wide combat arms battalion rotation program.
Geronimo returns to the United StatesEdit
On 1 July 1975 the lineage of Co C, 509th PIB was again reactivated, this time at Fort Rucker, Alabama, as the separate Company C (Pathfinder), 509th Infantry. The company was created by reflagging the existing 5th Infantry Detachment (Pathfinder), which had served at the post since 24 June 1963. (A Pathfinder presence at Fort Rucker can be traced back to 1960 with the activation of the Pathfinder Team, Company A, 2d Battle Group, 31st Infantry, to support the Aviation Center. It was authorized two lieutenants, an E-7, an E-5, four E-4s and four E-3s, by order of a letter from the Department of the Army to the Commanding General, Third US Army dated 10 March 1960 with the subject line "Reorganization of the 2d Battle Group, 31st Infantry." On 24 June 1963 the pathfinder unit was reflagged as the 5th Infantry Detachment.) Contrary to some erroneous accounts, Company C (Pathfinder) 509th Infantry was not created by transferring Company C, 1st Battalion, 509th Infantry from Italy to Fort Rucker; these companies were two separate units. There had already been a Pathfinder presence at Fort Rucker for 15 years. Even if the 5th Infantry Detachment (Pathfinder) had not already existed, the Army would not have reduced the strength of its forward-deployed Airborne Battalion Combat Team in Europe when sufficient manning was available in CONUS. Additionally, the organization and manning of an Airborne Rifle Company is different from that of an Airborne Pathfinder Company.
The size of C-509th varied depending upon funding and mission requirements. For example, documents on file at the United States Army Center of Military History in Washington, DC, indicate that when the company was activated in 1975 by replacing the 5th Infantry Detachment (Pathfinder), it was authorized 4 officers and 108 enlisted soldiers. Documents dated 22 September 1987 show the unit as still having 4 officers authorized but only 77 enlisted soldiers.
The lineage of 1-509th was reactivated provisionally in 1987 to serve as the OPFOR at the Joint Readiness Training Center at Fort Chaffee, Arkansas. The unit was activated at Little Rock Air Force Base in a formal ceremony on 21 May 1988. The unit was stationed at LRAFB because it provided modern quarters and facilities that Ft. Chaffee lacked, and it deployed on a per-rotation basis to Ft. Chaffee. The unit served and serves as the opposing force for American and Allied light infantry. In June 1993, 1-509th moved along with the Joint Readiness Training Center to Fort Polk, Louisiana. Since moving to Fort Polk, 1-509th Infantry has become an elite urban fighting training unit.
On 31 May 1993, the separate Company C (Pathfinder), 509th Infantry at Fort Rucker was reflagged as Company A (Pathfinder), 511th Infantry, reactivating the colors of a unit that had served with the long-inactive 11th Airborne Division and the short-lived (1963–65) 11th Air Assault Division (Test). The era of a Pathfinder unit at Fort Rucker ended on 31 October 1995 when A-511th was inactivated to meet budget cut ceilings.
Global War on TerrorEdit
Operation Iraqi FreedomEdit
In May 2004 Companies A and B, with attachments from Troop D of the 1st Battalion, 509th Infantry deployed to Iraq in support of Operation Iraqi Freedom II to the areas surrounding Baghdad to reinforce the 10th Mountain Division. One member of Troop D received the Silver Star for Valor in combat. Companies A and B and attachments returned in March 2005. During the deployment, Troop D and HHC continued to support JRTC exercises.
With the expansion of the Airborne force in Alaska from a single battalion (1st Battalion, 501st Infantry Regiment) at Fort Richardson, Alaska to a brigade 4th Brigade Combat Team (Airborne), 25th Infantry Division, the lineage of Company C, 509th PIB was again reactivated on 16 September 2005 as the 3d Battalion, 509th Infantry at Fort Richardson. The battalion deployed with the 4th BCT in support of Operation Iraqi Freedom in October 2006. The following is a media release from 10 November 2007, covering the battalion's work during OIF:
KALSU, Iraq — Paratroopers from the 3rd Battalion (Airborne), 509th Infantry Regiment based at Fort Richardson, Alaska have returned home after being deployed in Iraq since early October 2006.
After conducting numerous combat operations to include patrols, raids, and air assault operations with the Iraqi Army and Police, these Paratroopers are ready to stand down for some well-deserved rest, relaxation and getting re-acquainted with their families and friends. Since October 2006, the "Geronimos" from 3-509th Airborne have performed magnificently. During this deployment, the Geronimos were based out of Forward Operating Base Kalsu, located approximately 40 miles (64 km) south of Baghdad in Babil Province. On Christmas Day of 2006, part of the Battalion moved west of Baghdad to Al Anbar Province where they fought with the 1st and 2nd Marine Expeditionary Forces (Forward) against Al Qaeda in Iraq. While providing protection to the local citizens of the area, they were quite effective in helping the local populations create their own civil defense organizations, something that has become a model for success in stemming violence countrywide. During this time, the remaining Paratroopers also operated out of FOB Kalsu and FOB Iskandariyah to achieve similar goals. The Battalion consolidated in June at FOB Kalsu and began concerted efforts to stabilize their area of operation in Babil Province. In the months following, the Geronimos took on the role as a strike force, where they made great strides in fostering reconciliation between Sunnis and Shias in the cities of Haswah and Iskandariyah, and the surrounding areas. Operating "outside the wire", the paratroopers encountered many obstacles, including firefights with insurgents, improvised explosive devices, car bombs and explosively formed projectiles. They also captured numerous suspects, extremists, and terrorists considered to be high value targets, found a myriad of weapons caches, IED making facilities, al-Qaeda safe houses, and facilities used for detaining and torturing Iraqi citizens by performing countless operations, day and night, on the ground and by air assault.
Throughout their deployment, many of the Paratroopers received decorations for valor, achievement, and combat wounds. The 3-509th is part of the 4th BCT (Airborne), 25th Infantry Division also known as the "Spartan Brigade". After doing a most remarkable job as part of Operation Iraqi Freedom, these "Spartans" are looking forward to some quiet time and enjoying the safety and freedom that they have worked so very hard to keep for all American citizens.
Operation Enduring FreedomEdit
In February 2009 the Geronimo battalion deployed as a part of the 4th BCT (Airborne), 25th Infantry Division in support of Operation Enduring Freedom. A portion of the Valorous Unit Award citation is below.
For extraordinary heroism in action against an armed enemy. During the period 1 July 2009 to 30 November 2009, Headquarters and Headquarters Company, 3d Battalion, 509th Infantry Regiment and its subordinate units displayed extraordinary heroism in action against an armed enemy in support of Operation Enduring Freedom in the vicinity of East Paktika. The unit conducted a total of 302 combat patrols, and was responsible for 398 enemies killed, as well as the capture of 34 detainees. The company was also responsible for the safety of the populace of East Paktika during Afghan national elections. The unit's unrelenting perseverance and coordination allowed the unit to advance the struggle against the Taliban and contribute to the political and economic growth and development of the region. Headquarters and Headquarters Company, 3d Battalion, 509th Infantry Regiment's outstanding performance of duty is in keeping with the finest traditions of military service and reflects distinct credit upon the unit, the 25th Infantry Division, and the United States Army.
Operation Freedom's SentinelEdit
509th Infantry Regiment 
- 1st Battalion 
- 2d Battalion (Inactive)
- 3d Battalion 
1st BN, 509th Infantry Regiment
|Presidential Unit Citation (Army)||1944||for fighting in the LIEGE, BELGIUM|
|Presidential Unit Citation (Army)||1943||for fighting in the CARANO, ITALY|
|Meritorious Unit Commendation||2004||Company B, 1st BN, 509th IN - for fighting in Operation Iraqi Freedom|
|Superior Unit Award||2011-2012||for fighting in Operation Enduring Freedom-Afghanistan|
|Superior Unit Award||2009-2010||for fighting in Operation Iraqi Freedom-Iraq|
|Superior Unit Award||1993-1994|
3rd BN, 509th Infantry Regiment
|Presidential Unit Citation (Army)||1944||for fighting in the LIEGE, BELGIUM|
|Presidential Unit Citation (Army)||1944||for fighting in the CARANO, ITALY March 1944|
|Presidential Unit Citation (Army)||1943||for fighting in the CARANO, ITALY|
|Valorous Unit Award (Army)||2009||for fighting in PAKTIKA PROVINCE Operation Enduring Freedom-Afghanistan|
|Valorous Unit Award (Army)||2007||for fighting in BABIL PROVINCE Operation Iraqi Freedom-Iraq|
|Valorous Unit Award (Army)||2007||Company D, for fighting in Operation Iraqi Freedom-Iraq|
|Valorous Unit Award (Army)||2006||for fighting in AL ANBAR PROVINCE, Operation Iraqi Freedom-Iraq|
Additional Decorations Include:
- French Croix de Guerre with Silver Star, World War II for MUY EN Province
- Cited in the Order of the Day of the Belgian Army for action in the ARDENNES
- Cited in the Order of the Day of the Belgian Army for action at ST. VITH
- Personnel authorized to wear the insignia of the French 3d Zouaves Regiment
Campaign participation creditEdit
- World War II:
- Global War on Terror:
- Operation Iraqi Freedom - II
- Operation Iraqi Freedom - V
- Operation Enduring Freedom - X
Combat Parachute JumpsEdit
|List of 509th Parachute Infantry Regiment Combat Parachute Jumps|
|8 Nov. 1942||509th Parachute Infantry Battalion (PIB)||Torch||556||Algeria||Tafaraoui airfield, La Senia|
|15 Nov. 1942||509th PIB||Torch||300 - 350||Algeria||Youks les Bains|
|24 Dec. 1942||509th PIB, Hdqt's. Co. Two French paratroopers||32||Tunisia||El Djem|
|14 Sep. 1943||509th PIB||Avalanche||640||Italy||Avellino|
|15 Aug. 1944||1st Abn. Task Force (460th PFA, 463rd PFABn.; 509th PIB; 517th PCT; 551st PIB; 596th PCEng. Co.)||Dragoon||5,607||France||Cote d' Azur, Riviera|
Organization Timeline and Major EventsEdit
- Constituted 14 March 1941 in the Army of the United States as the 504th Parachute Infantry Battalion, consisting of HHC and Companies A, B & C.
- Activated 5 October 1941 at Fort Benning, Georgia
- Reorganized and redesignated 24 February 1942 as the 2d Battalion, 503d Parachute Infantry Regiment, consisting of HHC and Companies D, E, and F. Battalion deployed detached from the Regiment to England.
- 2/503 PIR arrived in England, and reorganized and redesignated 2 November 1942 as the 2d Battalion, 509th Parachute Infantry Regiment, consisting of HHC and Companies D, E, and F. Remainder of 503rd Parachute Infantry Regiment proceeded to Pacific Theater and separate Lineage with new 2nd Battalion.
- 2/509 PIR assaulted Oran and Youks-les-Bains Airfield in North Africa as part of Operation TORCH.
- TORCH assignment terminated, and unit attached to the 82nd Airborne Division on 15 November 1942.
- 2/509 PIR assaulted Sicily as part of Operation HUSKY on 9 July 1943.
- 2/509 PIR assaulted Salerno. Italy on 9 September 1943 as part of Operation Avalanche.
- 2/509 PIR parachuted onto Avellino on 14 September 1943. The unit was immediately engaged upon landing by German Forces, and was badly decimated. Unit was subsequently withdrawn from combat, and temporarily assigned as Security for Headquarters, 5th U.S. Army
- 2/509 PIR located at Venafro, Italy, and reorganized and redesignated 10 December 1943 as the 509th Parachute Infantry Battalion, consisting of HHC and Companies A, B, and C.
- Battalion arrived in France on 15 August 1944, for the start of Operation Dragoon.
- Operation Dragoon finished successfully on 14 September 1944, and Battalion released for
- 509 PIB engaged in Rhineland Campaign on 5 September 1944.
- 509 PIB relieved from Rhineland Campaign, and assigned to the 101st Airborne Division on 18 November 1944.
- 509th Parachute Infantry Battalion relieved From assignment to 101st Airborne Division 18 December 1944 and prepared for unit disbandment and personnel and equipment reassignment.
- 509 PIB Disbanded 1 March 1945 in France, with personnel and equipment reassigned to the 82nd Airborne Division.
- Unit Reconstituted 12 May 1947 in the Regular Army as the 509th Parachute Infantry Battalion
- Reorganized and redesignated 1 April 1963 as the 509th Infantry, a parent regiment under the Combat Arms Regimental System. 509th Infantry assigned to the 8th Infantry Division and was activated same date in Germany.
- 3/509th Infantry organic elements constituted 15 January 1972
- 3/509th Infantry activated 15 January 1973 in Germany
- 2/509th Infantry and 3-509th Infantry inactivated 31 August 1973 in Germany and relieved from assignment to the 8th Infantry Division
- 1/509th Infantry relieved 1 September 1973 from assignment to the 8th Infantry Division
- Headquarters and Headquarters Company, 3rd Battalion, 509th Infantry redesignated 1 July 1975 as Company C, 509th Infantry and activated at Fort Rucker, Alabama.
- 1/509th Infantry inactivated 1 July 1983 in Italy.
- 509th Infantry withdrawn 16 January 1986 from the Combat Arms Regimental System and reorganized under the United States Army Regimental System
- Headquarters, 509th Infantry transferred 18 December 1987 to the United States Army Training and Doctrine Command, and activated at Little Rock Air Force Base, Arkansas
- C-509th Infantry transferred 2 October 1988 to the United States Army Training and Doctrine Command and reorganized at Fort Rucker, Alabama.
- 509th Infantry transferred same date to the United States Army Training and Doctrine Command
- 1-509th Infantry activated 21 May 1988 at Little Rock Air Force Base, Arkansas
- 1-509th Infantry inactivated 31 May 1993 at Little Rock Air Force Base, Arkansas, and withdrawn from the United States Army Training and Doctrine Command.
- C-509th Infantry inactivated same date at Fort Rucker, Alabama, and withdrawn from the United States Army Training and Doctrine Command
- 1/509th Infantry activated 15 January 1994 at Fort Polk, Louisiana.
- A CO and B CO 1-509th Infantry deployed in June 2004 in support of OIF to Baghdad, Iraq. The two airborne infantry companies were attached to 2nd Brigade, 10th Mountain Division. A CO was attached to 2-14 IN and B CO was attached to 4-31 IN. Both companies returned from combat in March 2005.
- C-509th Infantry redesignated 10 December 2004 as Headquarters and Headquarters Company, 3rd Battalion, 509th Infantry.
- HHC, 3/509th Infantry Regiment assigned 16 September 2005 to the 4th Brigade Combat Team, 25th Infantry Division, and activated at Fort Richardson, Alaska
- September 2006: 3/509th IN (ABN) deploys in support of OIF
- December 2007: 3/509th IN (ABN) returns from OIF deployment
- February 2009: 3/509th IN (ABN) deploys in support of OEF
- March 2010: 3/509th IN (ABN) returns from OEF deployment
- December 2011: 3/509th IN (ABN) deploys in support of OEF
- September 2017: 3/509th IN (ABN) deploys in support of OFS
- Companies C and E activated on 12 September 2014 as part of 1st Battalion, 509th Infantry at Fort Polk, Louisiana.
- Breuer, William B. (1989). Geronimo! American Paratroopers in World War II (First ed.). New York: St. Martin's Press. pp. 5–6. ISBN 0-312-03350-8.
- Raff, Edson D. (1944). We Jumped To Fight (First ed.). New York: Eagle Books. pp. 30–35.
- "509th Infantry Regiment". The Army Historical Foundation. National Army Museum. Retrieved 31 May 2019.
- "509th Infantry Lineage".
- "509th Infantry Lineage".
- Gal Perl Finkel, How to win a modern war, The Jerusalem Post, 7 September 2016.
- United States Combat Jumps, GlobalSecurity.org, last updated 7 May 2011, last accessed 17 February 2013
- Units Credited With Assault Landings, General Orders No. 10, Department of the Army, dated 25 September 2006, last accessed 30 April 2017
- Headquarters, 1st Battalion, and 2nd Battalion organic elements concurrently constituted
- Barnard, Raymond. "Public Affairs Officer". Fort Polk Guardian. United States Army. Retrieved 22 September 2014.[permanent dead link]
- Doyle, Charles Hugo; Terrell Stewart (1988). Stand in the Door!: The Wartime History of the 509th Parachute Infantry. Phillips Publications. ISBN 978-0-932572-09-7.
- Jean-Loup Gassend (2014). Autopsy of a Battle: the Allied Liberation of the French Riviera August-September 1944. Schiffer Publications. ISBN 9780764345807.
|Wikimedia Commons has media related to 509th Infantry Regiment (United States).|