Operation: TREBUCHET

"Operation: TREBUCHET had been the UNSC's answer to Insurrectionists, and we'd just been folded into the far-ranging series of operations aimed to "pacify" the Outer Colonies."

- Gage Yevgenny

Operation: TREBUCHET was the Unified Earth Government's military response to the numerous civilian uprisings in the Outer Colonies known as the Insurrection. Spanning over ten years and encompassing multiple planetary systems, Operation: TREBUCHET involved numerous Marine units and many vessels from the UNSC Navy in an attempt to bring the dissenting insurrectionists in line, effectively crushing all resistance to the Earth's authority in the Outer Colonies. Beginning in 2513 with a large, armed uprising in the Eridanus system, it was one of the largest and farthest reaching operations known to have been conducted by the UNSC in its long history. With the beginning of the Human-Covenant War in 2525, Operation: TREBUCHET was temporarily suspended.

At first the aggressive response was widely accepted, however, as the fight dragged on and the theater of operations expanded, the continuing operation became extremely unpopular with the human civilian population. Operation: TREBUCHET eventually became the central conflict for Earth's premiere fighting force, the United Nations Space Command, only being ended with the massive genocide that followed with the Human-Covenant War.

Prelude
In June of 2494, UNSC Marine turncoat Colonel Robert Watts led a well-armed insurrectionist faction on Eridanus II and established their own secessionist government in the wake of the coup d'état. Equipped by defectors from the Colonial Military Administration, the rebels performed a well-planned and efficiently executed campaign of city bombings, political assassinations, and kidnappings. These attacks heavily impacted Eridanus II's shipping industry. Meanwhile, the rebels amassed a fleet of vessels from the CMA. The Eridanus Government officially requested aid from the United Nations Space Command in December of the same year. By January 2495, the insurgents had effectively taken control of the entire planet.

In January of 2496, UNSC forces finally responded to the government's requests and launched their campaign—Operation: CHARLEMAGNE—to retake Eridanus II, deploying a battle group to engage the makeshift insurrectionist defense fleet. Through a series of counter operations, the UNSC managed to break Watts' hold on the planet and splinter the insurgent factions allied with him by eliminating their leaderships. Eventually, the UNSC successfully regained control of the world, at the cost of four destroyers. Following the Eridanus II rebellion, Watts realigned most of the remaining insurgent factions that had aided him under his command and formed the United Rebel Front. The URF continued to engage UNSC and CMA forces on a number of worlds across the Outer Colonies.

Beginnings at Eridanus
"In 2513, an armed insurrection in this system was suppressed by the UNSC force—Operation: TREBUCHET."

- Doctor Catherine Halsey, referring to the insurrection on Eridanus II

Eventually, the United Rebel Front regained enough strength to attempt to overthrow the Eridanus Government a second time. Colonel Robert Watts, intending to use Eridanus II as a a base of operations for the URF and drag the Colonial Military Administration into a costly guerrilla war, launched an armed uprising on the planet. In 2513, fighting broke out throughout the Eridanus system, as rebels supporting the system's breakaway from the Unified Earth Government built a small navy of civilian craft and attempted to take over the system. However, the United Nations Space Command anticipated the attack and responded harshly, sending a fleet of carriers, cruisers, and destroyers to the system to combat the rebel fleet. The resulting battle pitted the UNSC against at least one hundred smaller rebel craft. The UNSC forces defeated their rebel counterparts in space with little difficulty.

Meanwhile, a ground campaign was fought on Eridanus II, as units from the 9th Marine Expeditionary Force were sent to the planet in force, hoping to capture leaders of the secessionist movement and pacify the population. One of these units, the 1st Battalion of the 21st Marine Division commanded by Lieutenant Colonel Ponder, was involved in a disastrous mission to try and capture a rebel leader—the second-in-command of the United Rebel Front—in Elysium City. When Ponder questioned the father of the rebel's wife, the man revealed himself to also be aligned with the URF and threatened to kill himself and his own daughter with a grenade. While Ponder realized the man was bluffing, an attached sniper drew an opposite conclusion and shot the rebel. The rebel pulled the grenade's pin out on reflex, which ended in the leader's family being killed and Ponder wounded and demoted.

Ultimately, the United Rebel Front was unable to establish a single stronghold on the planet and the UNSC managed to decimate most of their forces. Watts ordered for all URF forces to retreat from the planet, and the remaining rebel ships left Eridanus II and were pursued by the UNSC Navy until they fled into slipstream space. The remnants of their fleet regrouped under Watts' command and fled into the largest asteroid belt in the Eridanus system, where they established Eridanus Secundus. As the URF attempted to rebuild their strength, they would continue operating as pirates, raiding craft traversing the system.

Spread across the colonies
"A million casualties now, caught in the crossfire, since TREBUCHET started. No one's going to ignore that. The civilians will keep cheering the rebels on."

- Felicia Sanderson

By 2524, Operation: TREBUCHET had resulted in over one million civilian casualties. Meanwhile, Colonel Watts had created more rebel installations on planets throughout human-occupied space. The United Rebel Front proved to be difficult to route, and several other organized insurgent factions developed on other human colonies. Despite the best efforts of UNSC personnel, terrorist bombings continued and civilians were still caught in the crossfire, resulting in a growth of resentment directed towards the UNSC. As part of the operation, supersoldiers of the ORION Project were deployed on covert missions to engage insurgents. During one of these missions, Avery Johnson nearly succeeding in assassinating Watts.

Fighting continued, now in the Inner Colony system of Epsilon Eridani. When it was discovered that several major insurrectionist cells were operating on the industrial and populous colony world of Tribute, a Marine battalion was posted at the planet, commanded by Lieutenant Colonel Aboim and supported by the corvette with air support from AV-14 Hornets. The UNSC's initial attempts at eliminating the insurrectionists failed, leading to waves of bombings, assassinations, and UNSC raids in urban areas that resulted in high numbers of civilian casualties. During one of the battalion's operations on Tribute, the unit attempted to put a stop to rebel bomb makers. Two special warfare squads, led by Staff Sergeants Avery Johnson and Nolan Byrne, were involved in the disastrous attempt in stopping the bomb makers in June 2524. Although the rebel bomb makers were found and executed in a bomb shop in a struggling industrial town on Tribute, a truck lined with the bombs escaped to a Jim Dandy restaurant in the nearby Casbah City. When ordered to shoot the rebel with the bombs, Johnson's hesitation led to a rebel detonating her explosives. Three members of Byrne's team, as well as thirty-eight civilians, were killed. Byrne was critically injured in the explosion and Johnson was lightly wounded. Byrne and Johnson are pulled from the system, and later sent to Harvest. Although the insurgents initially enjoyed some degree of support from a part of Tribute's population, it soon became clear that the rebels were often the cause of violence on the planet and their support and popularity quickly decreased.

In the meantime, some insurrectionist cells resorted to bolder, more deadly tactics, such as the bombing of a civilian liner in orbit over Reach. The terrorist attack was listed as an accident by the Office of Naval Intelligence. The operation was abruptly concluded with the start of the Human-Covenant War after the disastrous first contact with the Covenant on Harvest. With the onset of the new war, Operation: TREBUCHET was temporarily suspended, but not officially terminated.

Aftermath and legacy
Though scattered Insurrectionist activity continued for a long time, the rebel threat was rapidly decreased when the genocidal Covenant destroyed most Outer Colony systems, glassing planets and killing every human they encountered. In the meantime, many of the rebels, seeing that the UNSC offered the only real protection against the overwhelming Covenant force, ceased to resist, and either submitted to the UNSC's control or hid themselves away from both UNSC and Covenant attack. Some groups of rebels survived free of UNSC control for as long as 2552. The majority simply continued their daily lives without interfering with the UNSC. Others even decided to offer dealings with the UNSC. However, it transpired that some were traps.

The rebel base in the Eridanus system was marked for further attack, but for some reason, likely due to the greater threat the Covenant posed, it was left alone and mostly forgotten until 2552 when Vice Admiral Danforth Whitcomb and a small crew including the artificial intelligence Cortana and several Spartans (including all but one of the team that attacked the base) returned looking for repairs. After being convinced to help by a Covenant attack, the rebels repaired the Ascendant Justice-Gettysburg to operational status, but the two ships were too badly damaged to be fully repaired before the Covenant returned. The UNSC forces were forced to abandon the rebels and the base and the rebels have been presumably destroyed.

By April 2553, Operation: TREBUCHET had been suspended for nearly thirty years, though the Venezian Militia still believed the Office of Naval Intelligence was willing to continue it. This led to the militia creating a large weapons pile-up and even capturing the Pious Inquisitor in the event that they needed to defend Venezia from the operation.

List of appearances

 * Halo: The Fall of Reach
 * Halo: Ghosts of Onyx
 * Halo: Contact Harvest
 * Halo Wars
 * Halo: Evolutions - Essential Tales of the Halo Universe
 * Dirt
 * Halo: Fall of Reach
 * Boot Camp
 * Halo: Combat Evolved Anniversary
 * Halo: Mortal Dictata