Swords of Sanghelios

"There was honor in our Covenant once, and there shall be again!"

- Thel 'Vadam

This faction is a splinter group of the former Covenant formed during the Great Schism, when the bulk of the Sangheili-led forces seceded from the Prophet-led hegemony. In November 2552, the Prophet of Truth had the Sangheili removed from their former position and replaced by the Jiralhanae as the Covenant's main military caste, resulting in an open war breaking out between the Jiralhanae-led forces loyal to the Prophets and the Sangheili. After the Sangheili learned the truth about the Halos near the end of the Battle of Installation 05, they allied with humanity on their mission to stop the Prophet-led Covenant.

As they no longer looked to the Prophets for leadership, the separatists initially lacked defined leadership, although Arbiter Thel 'Vadam and Shipmaster Rtas 'Vadum led their forces in the deciding battles of the war, with 'Vadam becoming the group's most prominent leader following the war's end. With the Covenant dissolved, the Sangheili returned to their homeworld and splintered into various factions, with the Arbiter and his policy of cooperating with humanity retaining a solid following. However, many Sangheili disagreed with his ideals, planning to overthrow the Arbiter and rise against humanity.

In the wake of the Covenant War, 'Vadam's group is often viewed as representing the Sangheili on the whole in their diplomatic relations with humanity. Similar to Jul 'Mdama's ideologically opposite Covenant group, 'Vadam's alliance considers itself—and is viewed by the UNSC as—the legitimate successor to the original Covenant.

Background
This disgruntled faction is led by the Arbiter Thel 'Vadam and Shipmaster Rtas 'Vadum. The group is mainly made up of Sangheili, along with some Unggoy and Mgalekgolo loyal to them. At the onset of the Great Schism, the separatists began fighting the forces loyal to the Covenant, led by the San 'Shyuum with their forces comprising Jiralhanae, Yanme'e, Kig-Yar and some Unggoy and Mgalekgolo loyalists.

The Arbiter's faction dismisses the Forerunners as false gods, rejecting both the Prophets' religion and the Sangheili's traditional faith. This has provoked the anger of many of their enemies, mainly the Servants of the Abiding Truth. Despite this, the Arbiter sought to build peace among the fragmented remains of the Covenant and remained as an ally to humanity. Indeed, the faction is the only known Covenant group to maintain diplomatic relations with the Unified Earth Government or, more specifically, the UNSC. By 2558, the UNSC's ambassador to them was Rear Admiral Horatio Temkin.

Origins
The High Prophet of Regret led a badly planned mission to Earth, against the wishes of the High Prophet of Truth, and was subsequently forced into the Battle of Earth, as he did not know that the planet was the human homeworld. He escaped to Installation 05, where he was killed by John-117. Regret's death was used as a justification by the remaining Prophets to replace the Sangheili with Jiralhanae as their protectors. However, this move resulted in great turmoil within the Covenant, with the Sangheili threatening to resign from the High Council.

Truth then gave command of the Covenant fleets, the post previously held by the Sangheili, to the Jiralhanae. Once there were enough of them in place, Truth secretly ordered them to commit a vicious genocide of the Sangheili (disguised as a retaliation to an Sangheili revolt against the other Covenant factions) so they may replace them in society. The Sangheili responded, with the help of factions of Mgalekgolo and Unggoy, and war broke out in High Charity with Jiralhanae and Sangheili fleets fighting each other in space around it. Later, most of the Sangheili Councilors were assassinated by the Jiralhanae at the behest of the Prophets.

An initial separatist movement was formed by the Sangheili Imperial Admiral Xytan 'Jar Wattinree on the Sangheili fortress world Joyous Exultation shortly after the Prophets' betrayal on November 3, 2552. Unlike 'Vadam's group, Wattinree's separatist Sangheili did not yet consider humanity their allies, dispatching a task force to Onyx to prevent Forerunner technology from falling into human hands. However, this fledgling alliance came to an abrupt end with the detonation of a NOVA bomb above Joyous Exultation and the deaths of the majority of the Sangheili leaders gathered there.

Sangheili-human alliance
The Unggoy were too indecisive to continue the rebellion and the true political motivation of the Mgalekgolo, if any, remains a mystery, although Mgalekgolo pairs could have followed the Sangheili they protect. The shaky-to-steady alliance between the separatists and their former foes, the humans, was forged entirely out of necessity. The UNSC forces were on the defensive, and both factions had two common enemies that wished for their extinction: the Covenant and the Flood. The alliance of circumstance was forged in the control room of Delta Halo, when UNSC Sergeant Major A. J. Johnson and the Arbiter were coerced to unite in order to prevent Tartarus, Chieftain of the Jiralhanae, from activating Installation 05. After that, the Arbiter persuaded the rest of the Sangheili to join humanity. While the two factions experienced some friction, they learned to work with one another for their mutual survival. By the end of the Human-Covenant War, the Sangheili fought alongside humans in battle and saved them from destruction.

The devastated UNSC Home Fleet defending Earth were glad to accept the help of the superior separatist warships. The Sangheili' understanding of Covenant equipment and combat tactics proved invaluable in the Battle of Installation 00. Recurrently the heroes of the battle, Thel 'Vadam and John-117, fought alongside one another many times in the desperate and long conflict.

Post-war
With Truth dead, High Charity destroyed, and Installation 00 essentially lost to the reborn Installation 04 firing, what remained of the Covenant was all but destroyed, with its member species divided into multiple factions. In the wake of the conflict, the Arbiter and his allies remained friendly to humanity and wished to build mutual peace, as they both had made tremendous sacrifices in order to stop Truth and the Covenant forces. On their homeworld, however, they were challenged by a resurgent faction of religious fanatics known as the Servants of the Abiding Truth, who viewed the Arbiter's allies as "blasphemers" and began an insurrection, secretly with the support of the UNSC's Office of Naval Intelligence. The Abiding Truth managed to gather a large amount of followers in a relatively short timespan; while the faction had a strong religious underpinning, many Sangheili had more practical motives for allying against the Arbiter, among them resentment toward humanity. Meanwhile, 'Vadam planned to visit each state to make his case for permanent peace with the humans they had battled for so many years. These reforms did not meet with universal approval. By January 2553, there was great dissent among disparate Sangheili factions, especially from the more devout believers in the Forerunners' divinity.

Avu Med 'Telcam, leader of the Servants of Abiding Truth, decided that an immediate assault on the state of Vadam was necessary. Along with nine ships and forces from Nuan keep and Rtova keep, 'Telcam commanded the assault from the frigate Unflinching Resolve. Eventually, however, the Unflinching Resolve suffered a direct hit and crash landed, though most of the crew, including 'Telcam, survived. Despite being caught off-guard it appeared as though the separatists would be victorious, however, news spread that he allowed humans to land on Sanghelios; this caused many keeps to ally with the Servants of Abiding Truth and the tide turned in their favor. The Arbiter was caught off guard and when his own reinforcements couldn't arrive on time, he reluctantly accepted Admiral Terrence Hood's offer for help in fending off the attackers. The tide turned when arrived over Sanghelios and destroyed the rebel destroyer Defender of Faith before finishing off the rebel ground forces with a MAC round. The, posed as a Kig-Yar pirate ship, destroyed a few of 'Vadam's ships in order to maintain the stalemate between the two factions, leaving the Arbiter with a Pyrrhic victory.

After the battle, Thel 'Vadam was in talks to visit the UNSC Infinity, a ship more powerful than any human ship during the Human-Covenant War. 'Telcam retreated to New Llanelli until he would be able to convince more keeps to join his cause. At some point, the Pious Inquisitor fell into the hands of the Abiding Truth. In turn, Kig-Yar pirate Sav Fel stole the Inquisitor, with the intentions to sell it on Venezia. With 'Vadam occupied with the ongoing civil war, Kilo-Five was tasked with returning the Inquisitor back to the separatists, though the ship was ultimately destroyed.

Over the next six years, the Sangheili continued to wage war against the remaining San 'Shyuum and the Jiralhanae. At first, the Sangheili were at a major disadvantage, as millennia of depending on the San 'Shyuum for technology meant that the Sangheili were unable to properly repair or replace the ships they lost in battle. The odds began to even out when the San 'Shyuum vanished and the Jiralhanae began to fall back into internecine conflicts.

Peace talks
In March 2558, the separatists attempted peace talks with the Jiralhanae chieftain Lydus on Ealen IV. Thel 'Vadam, with several Sangheili escorts, led the negotiations. Admiral Terrence Hood volunteered to moderate the talks between the two factions. However, the meeting was interrupted by a surprise attack by Covenant mercenaries under the command of Shipmaster Vata 'Gajat. Captain Thomas Lasky, Commander Sarah Palmer, and the Spartan-IVs defended the delegation and evacuated them from the chamber. When their evacuation ship was destroyed, the security detail proceeded to escort the delegates to a nearby parts depot.

Inside the repair depot, 'Vadam notified Hood and the rest of an old fortified redoubt in which they could take refuge in. Captain Lasky ordered Palmer and the protection detail to escort the delegation to the redoubt. As the party escaped the depot, they were intercepted by a Covenant Lich. Palmer quickly acted and threw her helmet filled with grenades and destroyed the Lich. The delegation stayed back as Fireteam Jackknife and their bodyguards went ahead to ensure the redoubt was safe for them to use as shelter. However, as the delegates entered the redoubt, Spartan Scruggs of Fireteam Jackknife had killed the Sangheili and Jiralhanae escorts and ambushed the group, holding Hood hostage. 'Vadam queried Scruggs on what his demands were; Scruggs stated that they would discuss them once his associates arrived. With the Covenant bearing on the site in force, the ambassadors' security detail discovered a craft they could use to evacuate. Thanks to the sacrifices of Fireteam Bailey, the delegation, Lasky and the surviving Spartans made it aboard Infinity, which rallied the feuding Sangheili and Jiralhanae fleets and forced 'Gajat's forces into retreat. Due to Shipmaster 'Gajat's attack, the negotiations were left in a standstill and little progress was made in furthering the peace between the Sangheili and the Jiralhanae.

Military structure
'Vadam's separatists have been observed to use the same ranks as used by the former Covenant Military.

Notable individuals

 * Thel 'Vadam, the Arbiter, leader of the Covenant separatists.
 * Rtas 'Vadum, Special Operations Commander and Fleet Master.
 * Unidentified Sangheili Shipmaster
 * Usze ‘Taham, operator within the Special Warfare Group and liaison to the UNSC.
 * N'tho 'Sraom, Special Operation operator.

Military assets
Thel 'Vadam's Covenant utilized much of the same equipment that the original Covenant used. Most Unggoy used the Type-25 plasma pistol and Type-33 Needler, while Sangheili personnel were typically armed with the Type-25 plasma rifle and Type-51 carbine. The Type-50 particle beam rifle remained as the separatists' main sniper rifle. Type-32 Ghosts and Type-26 Wraiths made up the majority of the faction's ground vehicles. Like the original Covenant the Type-26 Banshee remained as the main aircraft of the faction. Type-52 Phantoms were used as the main troop transports, although these sported a green color instead of the usual purple and utilized active camouflage. The faction's navy was composed of multiple s, s, and s.

Units
Fleet units
 * Fleet of Retribution
 * Shadow of Intent
 * Pious Inquisitor
 * Fleet of Righteous Vigilance

Ground forces
 * Several legions
 * Special Warfare Group
 * Covenant Special Operations

Trivia
Though the Covenant separatists were called "heretics" by the High Prophet of Truth, they should not be confused with the heretic faction led by the Sangheili Sesa 'Refumee and destroyed by Arbiter Thel 'Vadamee, although they do have the same goal and beliefs.

Gallery
 File:2973083-Medium.jpg|Two Sangheili Minors during the Battle of Installation 00. File:Schism_2.png|A Sangheili facing off a Jiralhanae in combat. File:Schism_3.png|A group of Sangheili charge towards Jiralhanae defenses. File:Schism_4.png|Sangheili warships and ground forces after a victorious battle. File:Escalation_schism.png|A Sangheili and Jiralhanae Captain Major locked together in combat. File:Thel 2558.png|Thel 'Vadam and escort on Ealen IV in 2558. 

List of appearances

 * Halo 2
 * Halo 3
 * Halo: Evolutions - Essential Tales of the Halo Universe
 * The Return
 * Halo: Glasslands
 * Halo: The Thursday War
 * Halo 4
 * Halo: Escalation
 * Halo: Mortal Dictata