- "The Taming of the Hunters, the Grunt Rebellion. Were it not for the Arbiters, the Covenant would have broken long ago."
- —Prophet of Mercy.
The title of Arbiter is the highest possible honor bestowed upon a Covenant Sangheili by the Hierarchs during a time of need. It is the greatest religious rank of the Sangheili, although councilor rank higher in political matters. The Arbiter acts as a sort of field general, going on missions for the Prophets and during incidents such as the Taming of the Lekgolo, the Unggoy Rebellion, the Human-Covenant War, and most recently, the threat of the heretics led by Sesa 'Refumee.
Arbiters are sent on highly perilous and suicidal missions in times of need. On these missions, the Arbiter is expected to die and to become another great martyr of the Covenant on their path to the Great Journey.
Originally, the title of Arbiter was given to the commander of the Sangheili military, and was considered a great privilege among the Sangheili. However, at some point between 2142 and 2525, the contemporary Arbiter, Fal 'Chavamee, refused to accept the Covenant religion and was branded a heretic by the Prophets. The resulting chain of events, which led to the deaths of both 'Chavamee and a high-ranking kinsman named Haka, led to the Prophets changing the role of the Arbiter significantly. The title was thereafter given to disgraced Sangheili in order for them to regain their honor by way of suicidal missions of great importance to the Covenant as a whole.
To most members of the Covenant, especially the Unggoy, the Arbiter is seen as a savior in times of dire need; their Sangheili peers consider them the living embodiment of the "Will of the Prophets" and refer to them as the "Blades of the Prophets". Every Arbiter is chosen during a time of great conflict, and inevitably dies in the course of their gravely important, though suicidal tasks. Their corpses - or presumably memorials in some cases  - are housed in identical caskets in the Mausoleum of the Arbiter. In the center of this room is a floating pod that contains the armor of the Arbiter when one is not currently appointed. This armor, while highly decorative, is fully functional as battle armor.
When an Arbiter is chosen, he is usually a highly skilled Sangheili warrior who, through either chance or misdeed, has severely disgraced himself in his line of duty. The rank of the Sangheili prior to becoming Arbiter presumably has no effect on the chance of becoming Arbiter, though higher-ranked Sangheili have better chances due to their more extensive experience and superior skill. The rank of Arbiter is considered a very prized reward, especially as it allows the individual to die honorably rather than be shamefully executed.
Though considered a commanding role of high esteem, the Arbiter is condemned to a life of suicidal missions to regain his honor. This includes the current Arbiter, Thel 'Vadam, who was branded a heretic for his failure to protect one of the sacred Halo rings from the so-called "Demon", SPARTAN John-117. Although the Arbiter is a singular warrior, he has the authority to give orders to other Covenant soldiers; this command can be likened to that of a UNSC four-star general.
Most Arbiters can be considered an equal to a SPARTAN-II supersoldier in both function and combat ability, as both are incredibly skilled in combat and vehicular activities and have the ability to instill morale in their troops.
Each Arbiter receives a unique set of armor that is built according to an age-old design. The very nature of the Arbiter means that they are sent on dangerous, often suicidal missions, where recovery of the corpse and the armor it wears may be impossible. The armor of the Arbiter is kept in the Mausoleum of the Arbiter until it is bestowed upon a new holder of the title. It is composed of a silvery-bronze colored metal with ornate engravings and metal work, indicating the Arbiter's ceremonial nature. However, it is fully functional as a combat suit, incorporating a Heads Up Display, an energy shielding system, and active camouflage. The armor incorporates a form-fitting bodysuit and blue restraining straps; these may be to prevent the Arbiter from removing the armor. Contrary to the claims of the Hierarchs, the Arbiters' armor is generally, if not always, replaced between wearers, as it is often irreparably damaged when an Arbiter is killed. This was the case with Ripa 'Moramee, whose body was pushed several kilometers off the Apex and was subsequently destroyed by a supernova.
The technology used in the armor is similar to the standard Sangheili Combat Harness, though it is of an older design. While modern Covenant active camouflage has a virtually unlimited duration, the Arbiter's camouflage lasts only for a few seconds, though still enough to give him a tactical advantage.
The armor may be subject to some small amount of customization. Ripa 'Moramee was taller than most Sangheili, at over 8'1, while Thel 'Vadam stands at 7'10''. Further, when first donning the armor, 'Vadamee lacked mandible guards or a shoulder-mounted light that he possessed after the Great Schism, where his active camouflage was also significantly upgraded. 'Moramee's armor, unlike 'Vadam's, featured a functionally unlimited capacity for using active camouflage.
 Known Arbiters
This is a list of all known Arbiters in chronological order.
- Unidentified Arbiter during the Taming of the Lekgolo, tasked with pacifying the Lekgolo resistance.
- Fal 'Chavamee - Arbiter during the period between the discovery of the Unggoy and the contact with humanity. 'Chavamee's refusal to accept the Covenant religion led to the rank of Arbiter being converted into a badge of shame.
- Unidentified Arbiter during the Unggoy Rebellion, tasked with quelling the uprising.
- Ripa 'Moramee - The seventeenth Arbiter in the line of Immaculate Succession who led Covenant forces on Harvest, Arcadia, and Shield 0459.
- Unidentified Arbiter during the Battle of Jericho VII.
- Unidentified Arbiter during the Fall of Reach. It is possible this Arbiter and the one at Jericho VII are the same.
- Thel 'Vadam - Arbiter who quelled the heretics led by Sesa 'Refumee and later led the Covenant Separatists during the Great Schism. Last Arbiter to be appointed prior to the Covenant's fragmentation; retains the rank as of 2553.
- In Halo 3, the Arbiter's armor is different from its appearance in Halo 2. The Arbiter's mandibles in Halo 2 are unprotected, while in Halo 3, the armor covers the mandibles. Also, the Halo 2 Arbiter armor is silver/gray, while the Halo 3 armor is closer in coloration to copper or bronze, though this is due to the improved lighting effects, as his armor is grey in levels with sparse light. Similarly, the Arbiter has a flashlight on his left shoulder, but it only works when playing with other players or a guest.
- The Arbiter was originally meant to be called the "Dervish". The name was changed because it might create an unintended parallel between the game and the real-life conflict between the Western World and the Middle East.
- In the Spanish language versions of Halo 2 and Halo 3, the Arbiter is called "Inquisidor". This is because the cognate "árbitro" means "referee", and the title would thus be lost in translation.
- Before Halo 2 was released, the Elite bipeds in Multiplayer had the armor of an Arbiter, but their armor was changed to the regular Elite armor.
- In Halo 2, the Arbiter's right side shoulder armor contains a mini sculpt of the Legendary Difficulty Skull. This can be seen in cut scenes and in co-op.
- An arbiter is someone who settles negotiations and disputes between parties. Decisions made by an arbiter are legally binding and endorsing.
 List of appearances
- Halo 2 (First appearance)
- Halo: Ghosts of Onyx (Mentioned only)
- Halo 3
- Halo Wars
- Halo Wars: Genesis
- Halo Legends
- Halo: Evolutions - Essential Tales of the Halo Universe
- The Return (Mentioned only)
- Halo: Glasslands
- Halo: The Thursday War
- ^ a b c Halo Wars, campaign level Escape
- ^ a b Halo Encyclopedia, page ???
- ^ Halo Wars instruction manual
- ^ Halo Encyclopedia, page ???
- ^ Halo 2, campaign level The Arbiter
- ^ Halo 3
- ^ Halo Wars
- ^ Frankie: This is quite late into the Covenant as a society, with most of the client species either absorbed or in the process of absorption...
- ^ Halo Interactive Strategy Game back side
- ^ Covenant players in the Reach campaign missions of the Halo Interactive Strategy Game play as an Arbiter.
- ^ Google Video: Halo 2 Bonus DVD : Multiplayer Featurette