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Operation: CHARLEMAGNE was an operation of the United Nations Space Command during the Insurrection, serving as a counter-attack against secessionist forces under the command of Colonel Robert Watts. The operation marked the first tactical deployment conducted by the ORION Project, as well as the only occasion where an entire unit of ORION operators was deployed together.
In June 2494, the UNSC Marine Corps turncoat Colonel Robert Watts had joined the Secessionist Union and rallied the insurrectionist movements on the human Outer Colony of Eridanus II, equipped by rebel sympathizers within the Colonial Military Authority's command hierarchy. Watts orchestrated a methodical and thorough series of assaults involving terrorist bombings, political assassinations, and kidnappings that heavily impacted Eridanus II's shipping routes. With the aid of their CMA contracts, the insurgents were even able to amass a small fleet of ships. The Eridanus Government officially requested aid from the Unified Earth Government in December of 2494 as chaos spread across the planet. By January of 2495, Watts and his insurrectionists had effectively taken control of the colony.
On January 12, 2496, the Unified Earth Government finally responded to the Eridanus Government's request for aid. The United Nations Space Command launched Operation: CHARLEMAGNE, deploying a large battle group of the UNSC Navy to Eridanus II. The battle group engaged the insurgent forces over the planet, an attack which succeeded at the cost of four destroyers. A number of subsequent counter-operations against the rebel forces began to break Watts' hold on the planet and splintered allied secessionist factions by eliminating their leadership.
Meanwhile, operatives of the recently resurrected ORION Project were deployed for the first time during Operation: CHARLEMAGNE. Inserted into the battle without being seen, the supersoldiers engaged the insurrectionists in a swift and silent attack that resulted in a decisive victory for the UNSC, with only one casualty among the ORION operatives and several crippling losses for the rebels; the ORION Project operatives saw the destruction of an insurgent military base on Eridanus II. The supersoldiers were promptly extracted from Eridanus II, again without being spotted. The operation extended to 2497, during which Marine forces deployed the SP42 Cobra for the first time.
As a result of Operation: CHARLEMAGNE, the Unified Earth Government succeeded in regaining control of Eridanus II. However, Watts and many of his insurrectionist forces were successful in escaping to the Eridanus system's asteroid belt, where they escaped capture and continued to operate against the UNSC. Watts subsequently took control of the insurgent factions that lost their leadership during Operation: CHARLEMAGNE, unifying them under a single banner as the United Rebel Front. Watts and the URF would later regain enough strength to strike at Eridanus II and the planet's government again in 2513, leading to Operation: TREBUCHET.
Meanwhile, the ORION Project, having completed both insertion and extraction during the operation without being seen by any survivors, fueled a range of conspiracy theories and media speculation. As the legend of these supersoldiers grew, it proved very helpful to the Office of Naval Intelligence's propaganda efforts in the following decades. The ORION operatives would go on to complete a number of successful operations, including Operation: VERITAS, in which high-level Colonial Military Administration officers were revealed to have loyalties with the Secessionist Union. Furthermore, the reveal of the CMA's role in arming the Eridanus rebels would lead to the organization's downfall and merger into the UNSC.
The operation was named after Charlemagne, a Frankish king who changed the political face of Europe in the 8th and 9th centuries CE.
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