John Spencer and Jayson Geroux | 10.28.22

The First Battle of Fallujah occurred between April 3 and May 1, 2004 during Operation Iraqi Freedom. The city of Fallujah is situated on the Euphrates River in al-Anbar province of Iraq, forty-three miles west of Baghdad. It is a densely populated, industrial city with a long history dating back to its development as a way station along ancient silk road branches that connected Baghdad to major population centers such as Aleppo, Syria. In 2004, Fallujah had an estimated population of 250,000 to 300,000 residents. The city was three kilometers square and consisted of over two thousand city blocks laid out in a grid pattern. The city had over fifty thousand buildings and structures, most of which were two-story concrete houses, but there were also some spacious homes, courtyard walls, half-completed dwellings, and multistory decrepit factories in industrial areas. It is bordered on three sides by prominent natural and man-made terrain features: the Euphrates River on the west, a rail network on the north, and a major autoroute, Highway 11, running the length of its eastern edge. Highway 10, a six-lane highway, runs through the center of the city. Elsewhere in Fallujah were wide boulevards, narrow streets, and alleyways—all filled, at the time of the battle, with heaps of garbage and wrecked automobiles.

Fallujah was known as “the city of mosques” because it contained over two hundred religious structures. It was an important center of Sunni Islam in Iraq. In fact, it was the imams who provided much of the insurgency’s leadership, as their embracing of extreme Wahhabism, resistance to foreigners, and claims that the Americans were present to destroy Iraq fueled their subordinates’ hostility toward the coalition. Local sheiks also wanted to consolidate their tribes’ positions in the post–Saddam Hussein era. Disaffected members of Saddam’s Baathist political party, ex-military officers, local criminals, and foreign fighters made up the enemy mix. The various group types meant that they operated from their own homes, had no centralized organizational structure, no command-and-control nodes, no communications to intercept, and no outright chain of command. The enemy had over six hundred weapons caches throughout the city, many of which were placed in the city’s mosques. The city grew to become an area of support and a safe haven for terrorist leader Abu Musab al-Zarqawi and his al-Qaeda in Iraq network. It was “the bright ember in the ash pit of the insurgency.”

The Battle

Before the First Battle of Fallujah, there had only been a sporadic American presence in the city. The intensive fighting that occurred in April 2004 would be the first major combat operation in the city. The battle occurred between a large number of insurgents, the US 1st Marine Division’s Regimental Combat Team-1 (RCT-1), and a variety of Iraqi security forces.

Several US Army units had rotated through Fallujah since the coalition invasion of Iraq in March 2003, including small forces from the 82nd Airborne Division. These thinly manned units, in relation to the size of the city for which they had been given responsibility, repeatedly used a “carrot and stick” approach: the former being a number of lucrative contracts for reconstruction projects and civic action initiatives, the latter being a number of aggressive raids against important enemy leaders and the quelling of protests. Although there were varying degrees of success with this approach there were never enough American forces to achieve progress in the city. It did not help that the local Iraqi police forces were unwilling to physically engage with the insurgents as a result. There were also a series of clashes between armed civilians in Fallujah and American soldiers that led to an increasingly volatile situation. Fallujah rapidly fell under the influence of insurgent factions and violence against the American presence was rising.

The 1st Battalion, 505th Parachute Infantry Regiment turned over responsibility for Fallujah to the 1st Marine Division on March 24, 2004. The commander of I Marine Expeditionary Force, Lieutenant General James Conway, wanted to try a different carrot-and-stick approach, having the Marines engage the civilian population while special operations forces eliminated insurgent leaders more discreetly. The hope for the Marines was that this approach would allow them to quickly turn over responsibility for the city to local Iraqi security forces, but even they did not know the true depth and size of the insurgency in the city.

Even before the Marines took full responsibility of Fallujah, the situation had not gone well. The Marines suffered eleven casualties just doing their familiarization patrols with the 82nd Airborne to understand the environment. Then it only took four incidents within two weeks to initiate the larger fight that would become the First Battle of Fallujah. First, on March 18, insurgents attacked a Marine command group along Highway 10. Eight days later, on March 26, an American unit was struck by a bomb in the city. Next, when Marine patrols were sent into Fallujah to make a safe route to transit through, they found an extremely contested environment and engaged in a thirty-six-hour series of firefights that left fifteen Iraqis dead.

The fourth event would come to be seen as the ultimate trigger for the larger battle. On March 31 four American contractors from the private military company Blackwater bypassed a Marine checkpoint in two trucks and drove into the city, possibly not understanding that they were heading into a hornet’s nest. They were met with a well-prepared, complex ambush from a number of insurgents armed with small arms and rocket-propelled grenades (RPGs). After the four men were killed, dismembered, and set aflame, two of the charred corpses were hung from the girders of a bridge over the Euphrates River while a large crowd cheered. The large group of mostly Iraqi men chanted threats like “Fallujah is the graveyard of Americans,” and within hours videos of the Americans hanging from the bridges were aired on broadcast news channels around the world. The following morning newspapers ran inflammatory stories with headlines such as “U.S. Civilians Mutilated in Iraq Attack” or “Barbarians of Fallujah.” Many of the stories compared the incident to the 1993 attacks in Mogadishu, Somalia where American soldiers were similarly mutilated and dragged through the streets.

Lieutenant General Conway and the 1st Marine Division’s commander, Major General James Mattis, recognized the event as a ploy by insurgent forces to provoke an aggressive coalition retaliation and that a large-scale operation would send the wrong message, unnecessarily endanger civilians, and ultimately fail to achieve the primary objective of locating the individuals responsible for the murders. Instead of an immediate massive response, Mattis wanted to allow time for a methodical intelligence preparation of the battlefield followed by a deliberate plan to take the city. However, senior political leaders in Washington, including the president, and US media organizations demanded an immediate, public, and heavy response. Lieutenant General Conway and Major General Mattis objected strenuously as they believed at this point that any operational counterattack seemingly based on revenge would play directly into the insurgency’s strategic goals. Moreover, there had been little time for the Marines to do the methodical intelligence preparation of the city or to conduct other steps of the military planning process. These arguments were overridden and the Marines were directed to execute the mission within seventy-two hours. On April 2, checkpoints were emplaced around the city to ensure no military-age males could not leave the city, with only those escorting families allowed out. On April 3, the 1st Marine Division was directed to conduct an offensive operation against Fallujah. A frustrated Major General Mattis requested but was denied US Army units from the theater reserve, an additional Marine regiment, and a tank unit, forcing him to later strip forces from other areas of al-Anbar province to conduct the operation. In retrospect, the denial of these additional forces was more than likely because the Americans as a whole were having to contain the counterinsurgency due to fighting that appeared to be spinning out of control and spreading to nearby Ramadi, as well as Mosul, Baghdad, and Najaf in early April.

The objectives for Operation Vigilant Resolve were to arrest the killers of the Blackwater personnel, clean out the foreign fighters, remove all heavy weapons from the city, and reopen Highway 10 for military traffic. Major General Mattis gave the mission to RCT-1, commanded by Colonel John Toolan, whose force initially consisted of 1st Battalion, 5th Marines (1/5), 2nd Battalion, 1st Marines (2/1), the regiment’s supporting tank company, an assault amphibian company, and an artillery battery. The plan was to have RCT-1 form a tight cordon around the city while raids were conducted against high-level insurgent leaders. Then larger raids and clearing operations by the two infantry battalions would be conducted inside the city to achieve the objectives of the overall operation and eventually turn the security of the city over to Iraqi security forces.

With less than three days to plan and execute the operation, it was hastily initiated on April 4. Small teams of special operations forces were initially tasked to move into the city to capture high-value targets while RCT-1 and Iraqi units moved into position to establish the cordon. This cordon included a plan for local Iraqi Civil Defense Corps and police personnel to establish seven interior checkpoints while Lieutenant Colonel Brennen T. Byrne’s 1/5 and Lieutenant Colonel Gregg P. Olson’s 2/1 established five outer blocking positions around the eastern and northern edges of Fallujah. The 1st Reconnaissance Battalion was deployed to conduct patrols to the north and east of the city to prevent any insurgent ability to fire mortar rounds or rockets at the Marines while D Company, 1st Light Armored Reconnaissance Battalion moved to cover the major highway on the eastern edge of the city. Naval Mobile Construction Battalion 74 had already begun constructing a dirt berm around southern Fallujah to further support the Marines’ ability to isolate the city.

The following day, April 5, RCT-1 began its assault on the outer edges of Fallujah. The attack plan had the two battalions entering the city from two directions hoping to pinch insurgents between the two fronts. Lieutenant Colonel Olson’s 2/1, with a company from the Iraqi 36th Commando Battalion, was to break into the northwestern suburb, the Jolan district, and advance south to southeast. Byrne’s 1/5—the same battalion that fought inside the Citadel of Hue in 1968—was to break into the southeastern industrial area in the Sin’a district, attacking north to northwest. The two battalions were provided a vast array of fire support that at different times included F-16 fighter jets, an AC-130 fixed-wing gunship, and AH-1W Cobra helicopter gunships in addition to the artillery fire support from 1st Battalion 11th Marines and their organic mortars. Each unit would also at some point be given a single platoon of tanks from C Company, 1st Tank Battalion, although in retrospect they were not enough to have a considerable impact in the opening phase.

The two infantry battalions immediately faced stiff resistance. The true number of enemy in the city was unknown because of the limited time to prepare, and intelligence estimates ranged from five hundred to six thousand insurgents. What the Marines found were streets blocked by empty cars and buses while the enemy moved in gangs of five to ten personnel, swarming into empty factory buildings to launch impromptu attack-by-fire ambushes with AK-47s and RPGs. They would then escape back out into the city or reposition to another building. In the daylight hours, these waves of gangs would gather in the city and move as a group to attack the Marines and it became clear that the enemy was better prepared than the Marines had expected. A summary of the battle bluntly described what the Marines encountered: “Insurgents surprise U.S. with coordination of their attacks: coordinated, combined, volley-fire RPGs, effective use of indirect fire. Enemy maneuvered effectively and stood and fought.” They also frequently combined their use of RPGs with improvised explosive devices.

Based on the stiff resistance and continuous heavy fighting RCT-1 was conducting in their assault and with little to no support from Iraqi forces, on April 6 Major General Mattis ordered reinforcements from RCT-7 to be sent into the city. The 620-man 2nd Battalion of the Iraqi Armed Forces had also been dispatched from Baghdad but after facing angry crowds of Iraqis en route, they refused to go to Fallujah and disintegrated as a unit. On April 7, Lieutenant Colonel Bryan McCoy’s 3rd Battalion, 4th Marines (3/4) joined RCT-1 in the fight and was assigned to break into the northeastern corner of the city, an area nicknamed “East Manhattan” by the Americans, and clear west.

The extent of the fighting was increasing. Also on April 7, a Marine supply convoy encountered a complex ambush of small arms, RPGs, and mortars from approximately forty to fifty insurgents. The Marines attacked into the ambush and killed twenty-six enemy fighters. To make up for the lack of adequate armor, the Marines continued to use large amounts of fire support for the remainder of the battle by having their mortars, artillery, F-16s, AC-130, and AH-1W Cobras firing on groups of enemy attempting to move on the infantry battalions.

The insurgents capitalized on the heavy fighting and destruction in the city with a concentrated information operations campaign aimed at making it appear that the Americans were destroying the city irrespective of civilian losses, that the airstrikes were imprecise, and that houses and schools were haphazardly bombed. Before the battle had started, the insurgents had allowed reporters and news crews, in particular Arab news agencies, to pass through their locations to report from deep within the city. One of the most influential of these was Al Jazeera, which positioned a journalist and crew in the city hospital where they broadcasted a constant stream of photos and videos of wounded civilians, including women and children.

The narrative of an overly destructive operation being conducted in Fallujah spread quickly. The real-time feeds of the high levels of destruction to media outlets included showing civilian casualties—the high civilian population had not really been given the chance to leave Fallujah given the short timelines—and the collateral damage to physical infrastructure had an immediate impact. American military and civilian leaders had initiated the operation without a cohesive information operation plan to counter the enemy narrative. As a result, the Iraqi population, government leaders and many in the international community strongly and publicly opposed the operation. Many senior Iraqi and American political leaders, including from the Iraqi Governing Council and key nations of the international coalition, began to debate and directly oppose the operation also. The Iraqi Governing Council eventually threatened to completely resign.

Due to the overwhelming negative narrative, rising opposition to the operation, military estimates on how much time it would take for American forces to accomplish the objectives, risks to the collapse of the Iraq Governing Council, and American plans for transition to Iraqi sovereignty, General John Abizaid, the commander of Central Command, and Ambassador L. Paul Bremer III, director of the Coalition Provisional Authority, decided to suspend all offensive operations in Fallujah.

On April 9, the Marines—who at that point had taken about a quarter of the outer parts of the city—were told to cease all offensive operations and to remain in place, but were also told by Lieutenant General Conway that the halt would be temporary and that the ceasefire would be for only twenty-four hours. On April 11, both 3/4 and 1/5 resumed their attacks, believing that they could break the resistance. However, within a short period of time they were once again ordered to halt. Major General Mattis was openly angered by the decision as he believed that the Marines had the enemy close to being destroyed due to the insurgents’ inability to receive supplies. He demonstrated this frustration publicly by paraphrasing Napoleon: “First we’re ordered in, and now we’re ordered out. If you’re going to take Vienna, then by God, sir, take it.” These views were shared by many of Mattis’s Marines.

For the next two weeks the Marines waited to return to the fighting and complete the operation while lengthy negotiations were being conducted by the various coalition, Iraqi Governing Council, and Fallujah tribal leaders and city officials. Concurrently, the Marines strengthened their positions on the outskirts of the city. Another battalion, Lieutenant Colonel Giles Kyser’s 2nd Battalion, 2nd Marines (2/2), was directed to join RCT-1 and was positioned on the southwestern outskirts of the city to prepare for the restart of the operation; the battalion would eventually begin a slow advance north close to the suburb the Americans had nicknamed “Queens.” The insurgents inside the city and in the surrounding villages had no orders to cease their activities so they attacked the halted Marines whenever and wherever they could. Many firefights and engagements occurred, in particular between April 11 and April 14.

The negotiations between the coalition and the different Iraqi actors finally concluded with the creation of a “Fallujah Brigade,” made up of former Sunni Iraqi military personnel who were to take over security of the city from the Marines. The hope was that this newly created unit would be able to seize and eventually bring peace to Fallujah to begin the process of bringing the city into the fold of broader Iraqi national control, although the US Marines believed that the Fallujah Brigade would be ineffective and side with the insurgency from the start. On April 28, the Fallujah Brigade assembled on the city’s outskirts, and on May 1, the Marines pulled back from the city; the First Battle of Fallujah had ended. In total, thirty-nine Americans were killed and ninety wounded in the battle. Approximately two hundred insurgents were believed to have been killed. The number of civilian deaths are impossible to fully know because of the lack of access to the city and enemy interests in increasing figures. Some estimates are as low as 220 while others estimate approximately six hundred, with half of those thought to be women and children.

Lessons Learned

A number of factors came into play during the First Battle of Fallujah that did not allow for American success. The operation lasted only six days before being halted and then haphazardly continuing in a suspended but active status for another three weeks. An analysis of the battle yields numerous strategic, operational, and tactical lessons.

The overarching strategic lesson from the battle is paradoxical. In a political context, senior political leaders should not react emotionally in war and direct immediate action against a densely populated urban area when conditions for success are not present. While the tragic loss of life and the public mutilation of the American contractors on March 31 was certainly unacceptable, to direct a course of action that was supposed to demonstrate a strong show of American force—yet in its hastiness, actually led to a weak one—only played into the insurgency’s hands and furthered the coalition’s strategic loss. Although the Marines’ leadership had a deliberate, methodical plan to respond to the atrocity, which included a thorough planning process that would eventually allow the Americans to take the city intelligently over a longer period of time, they were overruled by senior political leaders.

However, the American and international public reaction to the events in Fallujah seemed at the time to demand some type of immediate action. War has a strong political context and the Fallujah events opposed the perception of progress being made in the war in Iraq. It threatened US political and popular support for the entire war. Military leaders must grapple with understanding the political objectives of not only a single mission but linking them to broader national interests. The best military advice to respond to the events of March 31 was not as clear as “go now” or “do not go now, go later.” US forces lacked a clear understanding of the unique urban warfare challenges—enemy situation, status of population, information operations, political situation at all levels—present in Fallujah to provide the best alternatives or what would be required to set the conditions for success within an acceptable timeframe. Not only were the conditions not set militarily, but they were also not set politically with all relevant parties, from coalition political leaders to the Iraqi Governing Council.

The next strategic lesson is the vital requirement to conduct information operations in urban warfare—although it is a lesson that actually spans from the strategic to the tactical level. The enemy’s concentrated information operations campaign in Fallujah used multiple communication methods to take events out of context and make the Americans appear as the more unethical actors. American political leaders and military forces involved in the operation did not have a resourced or prioritized information operations campaign that would have rapidly refuted the insurgents’ propaganda. The Americans simply did not compete for the narrative. As a result, not only were they vilified internationally but senior Iraqi and American political leaders became apprehensive about how the battle was being executed and its impact on the strategic environment. This led to decisions being made to halt the operation and implement a completely different strategy, which also played into the insurgents’ plan as the operation’s ultimate cancellation allowed them to publicly declare that they were the victors. All plans for urban battles must include the time and effort to develop a comprehensive, well-planned information operations campaign that will dominate the information domain with timely, public access to the events of the battle as well as the ability to combat disinformation.

At the operational level, military forces must have an adequate amount of time to conduct an intelligence preparation of the urban environment. The Marines that would plan and execute Operation Vigilant Resolve had only been in Iraq in general and Fallujah in particular for less than a month. They did not have a clear understanding of the city or the enemy. The US political and media impatience that led to hasty reprisals against the insurgents who had killed American soldiers and contractors in March 2004 gave the Marines in Fallujah no chance whatsoever of understanding the city they were about to swiftly enter and fight through. Before any military forces consider conducting operations in an urban area, military leaders must provide political leaders the best advice on the length of time it takes to plan for and conduct urban operations; time must be set aside to understand both the city and the adversary. Intelligence sensors must be set in place, human intelligence collectors must gather information, and all information must be professionally analyzed to thoroughly understand the environment. This will inform decisions on what kinetic and nonkinetic effects must be achieved to win urban battles, both physically and cognitively across the levels of war.

At the tactical level, the battle of Fallujah highlighted the need for the appropriate number of forces and the right capabilities to conduct an attack on a densely populated city. The plan for Fallujah initially had just two infantry battalions entering to clear a city of up to three hundred thousand residents with an unknown number of enemy fighters. The Marines did not penetrate the heart of the city where the enemy had established its marshaling and support areas. The limited number of battalions coupled with minimum armor support only allowed the Marines to gain control of the outer edges of the urban area. US Army and Marine doctrine calls for more than a division to isolate and attack a city the size of Fallujah, but the coalition had only deployed a regiment, equivalent to an Army brigade. Specifically, doctrine states offensive urban operations “typically require a minimum of three to five times the force ratios needed for rural combat.” Also, the most effective force package for high-intensity urban warfare involves a combination of infantry, armor, engineers, artillery, and other enablers, with a symbiotic relationship enabling them to work together to defeat the enemy.

Lastly, at the tactical level, the First Battle of Fallujah shows the consistent urban challenge of protecting civilians. There will always be civilians in the urban battlespace. Military forces are required to prevent harm to civilians, critical infrastructure, and protected places. It is always prudent to remove as many civilians as possible from the battle area before the fighting begins. All urban operations must include proactive plans to communicate and facilitate civilian evacuations. With little preparation time, the Americans could not create those proactive plans, and even if they had been able to, the lack of an information operations for such messaging to be integrated into would have hampered efforts to broadcast to the city’s civilian population the need for them to at least flee the city as soon as possible before the fighting began. Thus, the city’s population was still present in Fallujah when the battle erupted. The insurgency capitalized on this by ensuring they exposed any civilian casualties in international broadcasts. The challenge for future urban battles will be that units must not only have comprehensive information operations messages, but also the proactive plans to safely remove civilians from an urban area. That safe removal of civilians and cooperation with all parties to ensure shelter, food, and medical support are provided so they will not become victims of the urban battle is a necessity.


The First Battle of Fallujah exposed some of the biggest challenges of urban warfare. Militaries must understand the unique attributes of the urban area, population, mission, information environment, length of time needed, and enemy attempting to prevent the accomplishment of the mission. The First Battle of Fallujah was a loss for the US forces not because of fighting capability, but due to insufficient planning, force ratios, information operations, and ultimately political support for the operation.

Colonel (CA) John Spencer is chair of urban warfare studies at the Modern War Institute, codirector of MWI’s Urban Warfare Project, and host of the Urban Warfare Project Podcast. He previously served as a fellow with the chief of staff of the Army’s Strategic Studies Group. He served twenty-five years on active duty as an infantry soldier, which included two combat tours in Iraq. He is the author of the book Connected Soldiers: Life, Leadership, and Social Connections in Modern War and coauthor of Understanding Urban Warfare.

Major Jayson Geroux is an infantry officer with The Royal Canadian Regiment and is currently with the Canadian Army Doctrine and Training Centre. He has been a fervent student of and has been involved in urban operations training for two decades and is an equally passionate military historian, having participated in, planned, executed, and intensively instructed on urban operations and urban warfare history for the past eight years. He has served twenty-seven years in the Canadian Armed Forces, which included operational tours to the former Yugoslavia (Bosnia-Herzegovina) and Afghanistan.

The views expressed are those of the authors and do not reflect the official position of the United States Military Academy, Department of the Army, or Department of Defense, or that of any organization with which the authors are affiliated, including the Canadian Army Doctrine and Training Centre, the Canadian Armed Forces and the Canadian Department of National Defence.