The Brutes
The Jiralhanae (Latin, Ferus Servire, translated to "Wild Slave"), known by humans as Brutes, are the newest members of the Covenant. They are a large, bipedal, ape-like species from Doisac. The Jiralhanae were the second Covenant species encountered by the humans following the Kig-yar raid on the freighter This End Up. They were also the first Covenant species encountered by the Harvest Colonial Militia. The Brutes have a profound hatred of the Sangheili, unmatched by any other feud within the Covenant, fired by the Jiralhanae's natural aggressive nature and the Sangheili's attitudes of superiority.
The Jiralhanae have been part of the Covenant since before the destruction of the UNSC agricultural colony on Harvest, and were always feared by the Sangheili for their monomaniacal behavior. The Jiralhanaes' plans to seize power over the Sangheili began with their alliance with the High Prophet of Truth during the Battle of Harvest and continued to gain headway until the eventual splitting of the Covenant. They eventually took the role of the Prophets' Honor Guards from the Sangheili after the Sangheili failed to prevent the assassination of the High Prophet of Regret by SPARTAN John-117 This culminated with the Jiralhanae replacing the Sangheili as the leaders of the Covenant military.
Despite their savagery, Brutes have proved intelligent enough to achieve spaceflight and space-faring status, though their warlike nature meant they quickly collapsed into civil war, and quickly afterward, fell back to their former pre-space status and learned nothing from the experience. The Brutes had recently concluded a mechanized war of attrition in which the many Master Packs fought and pummeled each other back to a pre-industrial state. When the Covenant discovered them in 2492, they had just rediscovered radio and rocketry. In their primitive state they were quickly defeated and absorbed into the Covenant.
Their warrior culture makes them formidable opponents, even for SPARTANs, and they were incorporated into the Covenant to serve as fierce guards for the Prophets and as heavy infantry.
Brutes are obviously carnivores, given their fearsome fanged jaws and propensity for violence. It has been stated that they feed on the flesh of their enemies, such as the Humans they face in battle, and have been seen eating the meat of a Thorn Beast, apparently considered a delicacy among Brutes. A Brute once stated he would have gladly devoured the future Arbiter, had he been allowed.
As part of the Covenant, Brutes were required as a prerequisite to convert to the Prophets' religion of worshiping the Forerunners. Previously, their culture revolved around the worship of totems and idols, but they made swift converts. The Brutes are now the most fanatical adherents to the Prophet's faith, although they seem to hold little concept of sanctity, evidenced by Tartarus' handling of the "Oracle".
Even at a glance, the Brutes are one of the most primitive members of the Covenant, at least technologically. Even though they employ Power Armor, and use a selection of the Covenant's weapons such as the plasma rifle, their native technology is crude; they often use weapons propelling spike-like or explosive projectiles. These weapons are often fitted with effective metal blades for melee combat.