Covenant fringe

The Covenant fringe was a collection of sapient species and civilisations scattered throughout the Orion Arm that were never fully integrated into the Covenant empire. Members of the Covenant fringe provided various strategic and infrastructure-related advantages to the Covenant, but posed no martial threat to the empire - instead held at arms-length and exploited for their unique strategic or infrastructural advantages.

Overview
The Fringe entities of the Covenant sat at the lowest tiers of the Covenant's species-based caste system. They were generally restricted to residing only on their respective homeworlds or in select remote locations, and were not afforded the same liberties as other citizens of the empire - even below the lowest caste species such as the Unggoy and Kig-Yar. In practice, these worlds were generally overseen by a local San'Shyuum executor or a contingent of Kig-Yar enforcers - the Fringe used as forced labour or in undignified utilitarian roles as they were not considered worthy of trading service for salvation in the Covenant military forces.

Due to their lack of frontline military service, and the general Sangheili lack of civil affairs record-keeping, the existence of the Fringe and its various civilisations remained nearly a total mystery to humanity throughout the Human-Covenant War. Following the end of the war in 2552, the United Nations Space Command and Office of Naval Intelligence have begun to gather the first pieces of intelligence on the exact nature and size of the Covenant fringe. However, most of these species have yet to be contacted by humanity, and many still remain a mystery entirely.

Following the collapse of the Covenant, the fate of the various fringe species' remains uncertain - though some believe they will simply pick up where they left off prior to the Covenant contact. Some member species of the fringe have a fragile status in the post-war years and some are subjected to persecution and enslavement by remnants of the former Covenant.

List of known fringe species

 * The Dazreme are another species in the fringe; their existence was kept secret from the other species by the San'Shyuum, who leveraged their unique knowledge of Forerunner technology to means unknown.
 * The Sharquoi are a species of hulking beasts so destructive that they were only rarely used by the Covenant military - as their deployments were just as like to leave Covenant forces in ruin as their enemies. Unbeknownkst to the Covenant, the Sharquoi were also once used by the Forerunners as one of many attempts to create a solution to fight the Flood during the Forerunner-Flood war.
 * The Yonhet from the small moon of Yonhe were a part of the Covenant fringe. When the species first came into contact with the Covenant, they were deemed militarily insignificant due to their small population and there was little value in considering the Yonhet as full signatories to the Covenant Empire. However, their talents and adherence to the Great Journey granted the Yonhet a high degree of tolerance within the Covenant. Thanks to the Covenant focusing on fighting humanity, the Yonhet were able to hide during much of the war and disperse, only to reemerge following the empire's collapse.

Production notes
In reference to regular questions about the Covenant fringe on the Halo Waypoint forums, 343 Industries' 2015 April Fools included the full list of species that made up the fringe: the Yonhet, Glacius (Killer Instinct), the Locust (Gears of War), and the Piñata (Viva Piñata).

List of appearances

 * Halo 2
 * Conversations from the Universe
 * Halo: Escalation
 * Halo: Nightfall
 * Halo: Envoy
 * Halo Mythos
 * Halo: Smoke and Shadow
 * Halo Infinite