Colonial Military Authority

The Colonial Military Administration or CMA was created by the Unified Earth Government in the early 2300s. Its original mission was to serve as the controlling body for UNSC ships and ground forces reassigned to colonial protective operations. However, over the years its role gradually became usurped by the UNSC.

Origins
Colonial duty was essentially a ceremonial function, primarily intended to placate the colonists' fears of pirates and marauders, so the UNSC felt a separate command—the CMA—would suffice to administer to these less important activities. At the time, NAVCOM and UNICOM believed that their own resources were better spent on activities within the Sol System. As the colonies spread and became more vital, NAVCOM and UNICOM tried to disband the CMA and usurp its role on a number of occasions, but the colonial command was adamant in protecting their turf. Their charter (approved by the UNSC) left little room for external maneuvering. Even so, by 2400 CE, NAVCOM and UNICOM were operating the Inner Colonies alongside the CMA.

CMA and the Outer Colonies
In response to the two encroaching commands, the CMA made the Outer Colonies their province, and tended to assign most of their forces to the periphery of the border worlds. They drew most of their recruits from the colonies and their soldiers often thought of themselves as frontiersmen, more bold and adventurous than their UNICOM counterparts. As Humanity spread, the CMA was at the forefront, helping colonists to tame worlds and protecting citizens from lawlessness in sparsely populated areas.

Split Allegiances
In the late 2400s, as brushfire wars began to crop up across the various colonies, tensions began to develop within the military hierarchy. Some soldiers of the CMA tended to sympathize with the plight of the colonists, while the soldiers of UNICOM held more allegiance to Earth.

The Demise and End of the CMA
In 2494, CE, secessionists within the Eridanus System began a campaign of violence against their Earth-sponsored government, using equipment supplied by traitors within the military, believed by many to be members of the CMA. The colony petitioned the UNSC for aid, and HIGHCOM dispatched a battle group that crushed the rebellion, though not so conclusively as to avoid continued dissent.

In 2497, the CMA's involvement with the rebels went public. This was considered the beginning of the end for the colonial military. Over the next few decades, citing security concerns, the UNSC gradually shifted the resources of the CMA to NAVCOM or UNICOM control, relegating the CMA to patrolling the most distant colonies and providing logistical support to remote stations.

By 2525, the CMA had been sidelined to the point of redundancy. Its budgets had been slashed and as such it was reduced to using obsolete and worn out vehicles, equipment and uniforms. Unlike the UNSC, CMA boot camp lasted just two weeks, which in the words of CMA veteran Gage Yevgenny was "enough to teach you how to use your weapon, salute, march, and drive a Warthog before they booted you right on out there."

NAVCOM/UNICOM Control
After contact was lost with Harvest, the CMA sent the UNSC Argo to investigate. It was also a CMA battle group that followed the Argo when it failed to report back. However, once the Covenant message was received, all CMA combat forces were placed under NAVCOM or UNICOM control "for the duration of the crisis". This reassignment essentially became permanent as the Human-Covenant War dragged on, and by 2552 CE, the Colonial Military Administration was little more than a fleet of navigational buoy tenders and remote fuel depots manned by wounded veterans and those unfit for combat service.

Trivia

 * The original super soldier program lie not with the UNSC, but with the Colonial Military Administration, which started its own program in 2321. Even though the program failed, it would be resurrected by the Office of Naval Intelligence as the ORION Project in 2491.