On 24 February 1941, at Guantanamo Bay, Cuba, then known as 1st Engineer Battalion, the unit was activated with the formation of the Headquarters and Service Company (H&S). All companies of the battalion were activated by 15 December 1941, just eight days after Pearl Harbor was attacked.

In August 1942, the battalion landed on Guadalcanal with the 1st Marine Division. Facing severe shortages of engineer equipment, the battalion used captured Japanese bulldozers and trucks to help complete the airfield and the defenses along the Marine perimeter. Serving as infantry at night, the engineers were kept busy repairing damage from Japanese bomber attacks.

The 1st Engineer Battalion fought in four other World War II campaigns: Eastern New Guinea, New Britain, Peleliu, and Okinawa. Typical of the role the engineers played was an attack that "C" Company participated in on New Britain in 1944. Facing a well entrenched enemy in swampy terrain, the engineers spent a torturous day building a corduroy road under direct enemy fire. In late afternoon, tanks were brought forward to lead the attack, but were unable to negotiate a 12 foot stream bank directly in front of the Japanese positions. Called upon to breach the final obstacle, two engineers moved forward on an unarmored bulldozer. Both were quickly killed, but another young engineer leaped aboard and managed to clear the way. That evening, the attack succeeded.

Following World War II, the battalion served in China on occupation duty, and then relocated to Camp Pendleton in 1947.

1st Combat Engineer Battalion deployed to Korea in 1950 and participated in the brilliant landing at Inchon. During that conflict, the engineers participated in ten campaigns, but were best known for helping to lead the famous "breakout" at the Chosin Reservoir.

On 1 May 1957, the battalion was redesignated as the 1st Pioneer Battalion. In October 1962, elements of the battalion took part in the Cuban missile crisis. On 1 May 1963, the battalion was redesignated as 1st Engineer Battalion.

The battalion sailed for Vietnam in 1965, remaining there until 1971. Providing a variety of close combat engineer support throughout I Corps, the battalion also took part in the battle for Hue City. On 31 March 1976, not long after its return to Camp Pendleton, the battalion was redesignated 1st Combat Engineer Battalion which more closely reflects its specific mission.

On 17 August 1990, the battalion arrived in Saudi Arabia and began unloading MPF shipping and preparing defensive positions during Operation Desert Shield. Six months later, the engineers breached Iraqi minefields and obstacles as they attacked into Kuwait on 24 February 1991, in Operation Desert Storm. The liberation of Kuwait was secure on 28 February 1991 and the engineers prepared to return to the United States.

1st Combat Engineer Battalion returned to San Mateo on 1 April 1991 and continued to provide engineering support to the 1st Marine Division.

From 29 December 1992 to 2 February 1993, 1st Combat Engineer Battalion (-) deployed to Mogadishu, Somalia, in support of Operation RESTORE HOPE.  During this period the battalion participated in the relief and security effort in Somalia.  Elements of 1st CEB fortified positions and improved defenses at the US Embassy, Mogadishu Airport, and Mogadishu Stadium.  Accomplishments during Operation RESTORE HOPE included 27 mines detected and recovered, 4 bridges reconnoitered, 55 road culverts constructed and emplaced, and 127 miles of road work and repair.

During 1994, 1st CEB conducted several significant operations and training exercises.  3rd Plt, Company A, deployed with 2/9 to Ft. Sherman, Panama, from 6-30 January.  Company B supported 5th Marines and 23rd Marines during GOLDEN PHEASANT ‘94 from 24 to 27 February.   1st CEB deployed 18 Marines to Kuwait from 6 to 24 April to participate in NATIVE FURY with 3/7.  1st CEB engineers constructed a mobile assault course at the Udari Range Complex, provided 3/7 with mobility/countermobility support and conducted cross training with the Kuwaiti Army Engineers. 

In August of 1994, 1st CEB provided a company (Rein) to the Wenatchee National Forest in Yakima, Washington, and the Kootenai National Forest in Libby, Montana, in support of Task Force Wildfire.  This support was to help efforts in containing the wildfires in Tyee, Washington, and Koocanusa, Montana.  A section of Marines were also deployed to the Persian Gulf in support of Operation VIGILANT WARRIOR, I MEF’s response to Iraq’s military maneuvers on the Kuwaiti border.

A platoon (Rein) was deployed to Chilliwack, Canada, in January 1994 in support of the Royal Canadian Engineers.  They conducted winter survival skills training, downhill skiing, and tactical movement in Arctic conditions.  In April of 1996, the Battalion deployed to the Marine Corps Mountain Warfare Training Center (MCMWTC) in Bridgeport, California, to conduct Mountain Warfare Training Course 4-96.  In May of 1996, elements of 1st CEB conducted JTF-6 missions in Imperial Desert, California.  The Marines were responsible for the capture of over 300 illegal aliens and over 500 pounds of Marijuana during the mission.  In September of 1996, a company-size element from the Battalion deployed to the Umatilla National Forest in Oregon to fight wild land fires as a part of a disaster relief task force (DRTF) to the National Interagency Fire Center (NIFC).

In December 1996, 1st CEB deployed two full line companies, Engineer Support Company (ESC), and elements of H&S Company for Operation STEEL KNIGHT VI.  This operation took place at Marine Air Ground Task Force Training Command (MAGTFTC) 29 Palms, and involved over 6000 Marines from every major unit comprising the ground combat element (GCE) of the I MEF MPF. 

The battalion deployed two platoons in July of 1999 to support BRIGHT STAR Exercise in Egypt, providing force protection to the ground troops participating in the exercise.  In June 2001, the battalion supported exercise RED REEF, Saudi Arabia, with one combat engineer platoon.  During the exercise the platoon conducted bilateral live fire training with the Saudi engineers from 2nd Battalion, 2nd Brigade, Royal Saudi Marine Forces (RSMF).  Additionally, the platoon landed in Aqaba, Jordan, for exercise INFINITE MOONLIGHT.

Following the September 11, 2001 attacks on the United States, a platoon with the 15th Marine Expeditionary Unit (MEU) deployed to Afghanistan and supported the seizure of Bagram Airbase during Operation ENDURING FREEDOM. 

In early 2003, 1st CEB deployed to Kuwait for Operation IRAQI FREEDOM.  In March, 1st CEB combined with 2d CEB as the combat engineer element for the 1st Marine Division (Rein) and moved into Iraq in support of I MEF’s march to Baghdad.  Four combat engineer platoons remained in Iraq until late 2003 to provide support to the infantry battalions still located in the cities of Karbala, Diwaniyah, An Najaf, and As Samawah for Stability and Support Operations (SASO).  By October 2003, all of the remaining platoons redeployed back to Camp Pendleton from Iraq.

1st CEB’s companies returned to Iraq in March of 2004.  Both Company C (Rein) and Company B (Rein) supported 1st Marine Division’s Regimental Combat Teams (RCTs) 1 and 7 in Al Anbar Province.  Two reinforced engineer platoons attached to MEUs also supported combat operations in Iraq.  In July, the Battalion deployed a detachment to provide advanced IED training in theatre.  By October 2004, Company C and Company B redeployed back to Camp Pendleton, CA.

In 2005, 1st CEB platoons with both the 11th and 15th MEUs supported combat operations in Iraq.  In March, an additional platoon joined combat operations in country.  In September, Company C (Rein) deployed to western Al Anbar Province in support of RCT 2.  Company C participated in Operation STEEL CURTAIN and operations in the vicinity of Haditha, Hit, Haqlaniyah, and Barwanah.  In February 2006, Company B deployed to Al Anbar Province in support of RCT 5.  Company C returned to Camp Pendleton in March 2006, and subsequently deployed back to Iraq in August/September to relieve Company B in Fallujah in support of both RCT 5 and 6.  

From January to December of 2007, two line companies, Company C (Rein) and Company B (Rein), were deployed in support of Operation Iraqi Freedom (OIF). Company C (Rein) deployed ISO RCT-5 headquartered out of Camp Fallujah and Company B (rein) deployed ISO RCT 2.  3d and 1st Platoons from Company A were also deployed in support of OIF while attached to the 15th and 13th Marine Expeditionary Units (Special Operations Capable) MEU (SOC), respectively.  2d Platoon, Company A conducted pre-deployment training and then attached to the 11th MEU to begin workups.  Engineer Support Company and Headquarters & Service Company both provided Marines and equipment to the deployed reinforced line companies and provided support to home station training for the units preparing to deploy.  Through coordination and direction from Headquarters Marine Corps (HQMC), the Battalion began forming a new company – Mobility Assault Company (MAC), formerly Company D (a cadre line Company) but with a new mission of armored assault breach

ing.  This Company was initially formed around two future systems: the Assault Breacher Vehicle (ABV) and Joint Assault Bridge (JAB).  Subsequently, it was decided to incorporate the motorized route clearance mission that was developed in theatre and has become a critical engineer requirement in both OIF and OEF campaigns providing mobility to the Division and Regional Commands.

From January through June 2008, Company C (Rein) and Company A 3d CEB (Rein), were deployed in support of Operation Iraqi Freedom (OIF).  Company C (Eein) deployed in support of RCT 2 in Al Anbar Province, ending their deployment by being relieved by Company A 3d CEB (Rein).  2d and 3d Platoons from Company A were also deployed while attached to the 11th and 15th Marine Expeditionary Units (Special Operations Capable) MEU (SOC), respectively.

In July 2008, the battalion executed Exercise Summer Heat, a multi-battalion Alternate Training Venue in 29 Palms, CA.  During this month, 3d Platoon, Company A, was deployed with the 15th MEU and en-route to Jordan.  Company C began reorganization, forming two line platoons (1st and 2d Platoons).  1st Platoon and Support Platoon, Company A, 3d CEB, conducted military operations in Iraq to include Anti-Terrorism Force Protection (AT/FP) improvements and demilitarization efforts.  2d and 3d Platoons, Company A, 3d CEB, conducted missions in Afghanistan to include raids, route clearance, cache sweeps, and AT/FP improvements. 

In January 2009, the battalion was officially notified that they would be deployed to Afghanistan in support of Operation ENDURING FREEDOM in Afghanistan as a battalion forward in its entirety.  This would be the first time since Operation Iraqi Freedom (OIF) 1 that the battalion headquarters would be deployed together.  The Battalion Sappers conducted Sapper Squad Leader Course 01-09.  During this month, 1st Platoon, Company A, was deployed with the 11th MEU.  1st and 2d Platoons of Company C began their deployment in support of OIF.   Company B 1st and 2d platoons and the company headquarters remained deployed to Iraq in support of OIF 08.2. 

During the months of July through October 2009, the 1st Combat Engineer Battalion (1st CEB) operated with a Headquarters and Service Company, an Engineer Support Company, and a Mobility Assault Company in support of Operation ENDURING FREEDOM 9.1 in Afghanistan.  The three Combat Engineer Companies: Company A, Company B, and Company C remained behind at Camp Pendleton, California.  During the months of November through December 2009, 1st CEB operated with an H&S Company, ESC, MAC, and the three Combat Engineer Companies: Company A, Company B and Company C at Camp Pendleton, California. 

During the months of January through June 2010, 1st Combat Engineer Battalion (1st CEB) conducted pre-deployment training with H&S, Engineer Support Company, MAC, and Company C for an upcoming deployment in support of Operation Enduring Freedom in Afghanistan. Company A, 1st Platoon conducted a pre-deployment training cycle to prepare the platoon for their upcoming deployment with the 13th MEU. During the months of January through June 2010, 1st CEB operated with an H&S Company, Support Co, MAC, and the three Combat Engineer Companies: Company A, Company B, and Company C at Camp Pendleton, California.

During the month of February, Company B deployed to Afghanistan in support of Operation Enduring Freedom 10.1. Its primary mission was to provide mobility, countermobility, and survivability support to Regimental Combat Team 2 and Regimental Combat Team 7. Company B had 2d Platoon, 4th Combat Engineer Battalion attached in direct support to 3d Battalion, 7th Marines. Company A, 2nd Platoon returned from a deployment with the 11th MEU which lasted from September 2009 to April 2010. During the month of May 2010, Company A, 3d Platoon deployed with the 15th MEU.

In October of 2010, 1st CEB deployed back to Afghanistan in support of Operation ENDURING FREEDOM 10.2 with Company C, Mobile Assault Company, Engineer Support Company, and Headquarters and Service Company.  In addition, the Battalion was augmented with a company headquarters staff from Combat Engineer Company, Combat Assault Battalion, Okinawa Japan, and augmented with the 309th US Army Reserve Engineer Company based out of Arden Hills, Minnesota serving in a Route Reconnaissance and Clearance (R2C) role.

On 8 May 2011, 1st CEB returned from Afghanistan to begin their pre-deployment training for the next deployment in support of OEF 12.1. 1st CEB conducted a battalion exercise at Marine Corps Mountain Warfare Training Center (MCMWTC) in Bridgeport, CA from 8 September to 7 October. For the first time in the modern era, a CEB deployed to MCMWTC in order to conduct a training exercise. CEB assisted the training and support cadre of MCMWTC to develop a training scenario tailored to missions more specific and inclusive of an Combat Engineer Battalion. 1st Platoon, Company A deployed in support of the 11th MEU on 14 November. 1st Platoon, Company B deployed to Afghanistan in support of 2d Battalion, 6th Marine Regiment on 27 November initiating the staggered deployment of the battalion spread across six months. Subsequently, 3d Platoon, Company B deployed to Afghanistan in support of 2d Battalion, 9th Marine Regiment on 3 December along with Company C headquarters, 1st Platoon, Company C in support of 1st Battalion
, 8th Marines, 3d Platoon, Company C in support of 2d Battalion, 5th Marines 2d Platoon, Company C in support of 1st Battalion, 7th Marines, and 2d Platoon, Company B in support of 3d Light Armored Reconnaissance Battalion.

In April of 2012, 1st CEB (-) (Rein) again returned to Afghanistan in support of Operation ENDURING FREEDOM 12.1. The battalion main body consisted of H&S, MAC, ESC, and a reserve company attached from 4th Marine Division as an additional route clearance company – Company E, 4th Tank Battalion.





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1st Marine Division