The SPARTAN project was a secret UNSC Office of Naval Intelligence Section 2 project designed to create human supersoldiers. The program began with the goal of combating human insurgency in the Outer Colonies, but shifted its focus to fighting the Covenant once first contact was made. Spartans are notable for being extremely effective battlefield combatants, with even a single soldier able to turn the tide of a battle. The project had four phases:
- Project ORION, an aborted program involving enlisted personell and early attempts at genetic modification
- SPARTAN-II, a much more comprehensive program that created the Master Chief. MJOLNIR armor is designed for the SPARTAN-IIs, greatly increasing their abilities.
- SPARTAN-III, a larger scale version of the SPARTAN-II program, Spartan-IIIs were trained quicker, and equipped with poorer equipment than their Spartan-II cousins. Spartan-IIIs were used as disposable soldiers for operations too dangerous for UNSC marines or ODSTs- operations wheremost Spartan-IIIs were wiped out.
- SPARTAN-IV, a program developed toward the end of the Human-Covenant War that will feature in Halo 4.
A project ORION dossier
In 2491 the first supersoldier program was initiated. The UNSC Office of Naval Intelligence (ONI) concluded that the instability of the outer colonies would result in widespread rebellions and, if not dealt with, spark a wholesale separatist war. The ORION project (retroactively renamed SPARTAN-I) was the first generation of warriors. Very few specifics of ORION are known, other than the fact that it involved 'enhancing' ordinary soldiers, and that Avery J. Johnson was one of the test subjects. Ultimately, the effects weren't as pronounced as the scientists had hoped, and ORION was discontinued, but the project was successful enough to gather the necessary information for a second phase, Project: SPARTAN-II.
A SPARTAN-II squad
Following the closure of Project: ORION, work began on a second, more thorough supersoldier program. This was SPARTAN-II, destined to become one of the most significant military developments in human history. The program was much more ambitious and well funded than Orion, calling for close to a decade of military training from childhood followed by improved genetic modification, and, eventually, powered MJOLNIR armor suits. The comprehensive program was designed to create the finest fighting force humanity had ever seen.
With the threat of Outer Colony insurrection growing increasingly worrying, scouting for candidates began in 2511 and continued through 2517, when the program officially began. All recruits were children near the age of six, both male and female, who were forcibly conscripted into the program. The process of scouting took so long because the recruits had to match very specific genetic markers, and have suitable temperaments. The children of ORION test subjects were considered early, but it is unknown if any ultimately made it into the Spartan-II program.
In 2517, the 75 child candidates who had been secretly selected for the program were abducted by ONI agents and replaced with flash-clones without the knowledge of anyone in order to conceal the conscription. The children were taken to the planet Reach to begin their rigorous training regimen. Under the tutelage of Dr. Catherine Halsey and Chief Petty Officer Mendez, the children honed their minds and their combat abilities, becoming near-perfect soldiers. The program heavily emphasized teamwork and the importance of thinking in combat, which led to the Spartan-IIs forming extremely close interpersonal bonds. By the age of 12 the Spartans were regularly beating their marine handlers in wargames. By the close of their training in 2525, the Spartan-IIs were already the deadliest human fighting force in existence, and the UNSC was confident that their deployment would put a quick end to the insurgency.
At the close of their training, all 75 Spartan-IIs were subject to genetic augmentations designed to increase their combat ability. Due to inherent dangers with the process, 30 of the Spartans died in augmentation, with an additional 12 crippled to the degree that they could no longer serve as combat personnel. The remaining 33 Spartans benefited greatly from the augmentation, receiving:
- Enhanced reflexes
- Increased speed
- Increased muscle and bone density
- Greatly improved eyesight
- Increase in creativity and intelligence
Some months after augmentation, the Spartans took on their first mission against insurrectionists, successfully infiltrating a rebel base in an asteroid belt and capturing a rebel leader, Colonel Robert Watts. At the same time, contact with the Covenant was made, and the Spartans were redirected from their original directive in order to fight the Covenant. As the final step to becoming fully operational, every active Spartan-II was fitted with MJOLNIR Mark IV armor.
For the next 27 years the Spartans fought the Covenant across the galaxy as the UNSC was inexorably pushed back, losing planet after planet. Although the Spartans could match any Covanant force on the ground, UNSC battleships couldn't match the firepower of the Covenant fleet. Only a small number of Spartans died in the fighting [impossible to determine the correct number due to a huge number of contradictions throughout different sources].
MJOLNIR Power Armor Mark V
In 2552 all remaining Spartan-IIs were recalled to Reach and were fitted with upgraded MJOLNIR Mark V armor, which included energy shielding and a host of other improvements. The Spartans were given a mission to capture a Covenant cruiser, locate the Covenant homeworld, capture a leader and force a truce. Before the mission could get underway however, Reach came under attack by Covenant forces and the Spartan-IIs were deployed to defend it.
The Master Chief remained in space to destroy a computer with Earth's location on it while the rest of the Spartans went groundside to protect generators providing power to the orbital defense grid. The Spartans failed to hold the generators and the Covenant destroyed the planet from space, killing most of the Spartan-IIs, although some managed to escape to underground facilities. The Master Chief left Reach on the Pillar of Autumn believing himself the last surviving Spartan.
Though it began as a top-secret project, some years into the Human-Covenant War the program went public as part of the UNSC propaganda effort. In order to make Spartans seem more mythical than they already were, a directive was issued that no Spartan could be declared KIA, which led to the process of all dead Spartan-IIs being classified only as MIA, in order to avoid the morale problems associated with the Covenant killing the strongest humanity had to offer.
Throughout the UNSC there were mixed reactions to the existence of the Spartan program. Many admired it, and the soldiers serving, especially since the Spartans were decorated with literally every medal available except for being a POW. However, many viewed Spartans as unnatural and unhuman, something no doubt encouraged by the cold, operational demeanor of the Spartans. ODSTs in particular disliked Spartans, as ODSTs viewed themselves as the best of the best, and Spartans were a challenge to them.
As is tradition in the military, the Spartan-II soldiers have their own emblem to distinguish their company from the others in the UNSC Marine Corp. The emblem is based on an old coin given to John-117 as a young boy by Dr. Catherine Halsey .
The design is a modification to the traditional American eagle depicted on official United States documentation, currency and, most importantly, The Great Seal of the United States. On the seal the eagle is shown beneath a grouping of stars representing the original American colonies and carrying arrows and an olive branch representing war and peace. However the Spartans have modified the emblem into the version shown to the right. Now the eagle carries arrows and a lightning bolt representing power and speed, the hall marks of a Spartan-II soldier. The other change from the coin is the removal of the group of stars replacing it with a single star representing Sol, cradle of humanity and the center of the UNSC.
After the second class of Spartan-II soldiers was canned due to budgetary reasons, the UNSC focused their resources on the new SPARTAN-III program, led by Colonel James Ackerson, a rival of Dr. Halsey's. The SPARTAN-III program mostly followed the structure established by the SPARTAN-II program. Unlike SPARTAN-II, whose "recruits" were actually kidnapped prepubescent children, the subjects in SPARTAN-III were war orphans in their mid teens, recruited from refugee populations and run through a grueling multi-year training program on the planet Onyx, a secret UNSC base, then deployed into the field to fight in the war. Their existence was kept classified top secret, even though the SPARTAN-II program had gone public with extremely positive results.
A SPARTAN-III in SPI armor
The United Nations Space Command brass viewed Spartan-IIIs as short term solutions to pressing problems, and often threw away their lives en masse to take out high priority targets. Many missions ended with 100% casualties for entire Spartan-III companies. Fitting this use, the UNSC did not see fit to equip them with expensive MJOLNIR armor suits, instead opting for the newer Semi-Powered Infiltration (SPI) armor, a model capable of active camouflage but lacking energy shields and the strength enhancements of MJOLNIR.
The day to day operations of training Spartan-IIIs were handled by a graduate of the SPARTAN-II program, Kurt-051, and CPO Mendez, who also helped train the Spartan-IIs. Spartan-IIIs were trained in "companies" of 300-350 children for roughly five years during early adolescence. The training was quite similar to that of the Spartan-IIs, but due to it's abbreviated nature was not as effective in certain areas. After completing the training, the Spartan-IIIs underwent genetic modifications, and were immediately sent into the battlefield to fight the Covenant. This training resulted in extreme social withdrawal for some Spartan-IIIs, making it difficult for them to interact with others outside the program, especially civilians and the human insurrectionists they were occasionally deployed against.
The Spartan-IIIs received some different genetic augmentations than the Spartan-IIs, in part due to advancing technology and in part due to the different objectives of the Spartan-III program. Due to newer technology and experience gained from the Spartan-II program, the survival rate for Spartan-III augmentation was 100%. The Spartan-III augmentation resulted in:
- Virtually unbreakable skeletons
- Increased muscle density and strength
- Improved eyesight and night vision
- Much improved reflex reaction time
After two complete companies of Spartan-IIIs were wiped out in operations, a new drug was added to Spartan-III Gamma Company that increased aggression, strength, and pain tolerance in extremely stressful situations. However, this drug decreased the mental stability of the Spartans (already a problem), and could cause brain damage if not properly counteracted.
Specialized Spartan-III Units
Despite their general use as disposable soldiers, some Spartan-IIIs were separated from their peers and given more advanced training, better resources, and more specialized roles, putting them closer to their Spartan-II brethren.
The Headhunters were a group of two-man Spartan-III teams tasked with the sole purpose of creating chaos behind enemy lines by hitting supply depots, sabotaging ships, assassinating enemy leaders and any other means possible. These units specialized in guerilla tactics and were often dropped in areas with little to no hope of rescue.
NOBLE is the closet Spartan-III comes to matching the SPARTAN-II program. Hand picked by Kurt-051, NOBLE team is a group of SPARTAN-IIIs who have been mixed and matched from different Spartan-III companies to form a fireteam capable of taking on any mission. The Spartan-IIIs of NOBLE are unique in that they are equipped with MJOLNIR suits and treated as vital assets, not a disposable fireteam to be used and discarded. NOBLE team also includes a Spartan-II, Jorge-052
All four SPARTAN projects have had an impact on the series. Sergeant Avery Johnson, a supporting character in the main Halo trilogy (and a playable character in Halo 3: ODST's Firefight multiplayer mode), was one of the soldiers selected for 'improvement' in the top secret ORION project. It is unclear what specific improvements were made to the members of the ORION project, but it can be assumed that they are slightly more physically able than the average soldier. In addition, it has been confirmed that Johnson's SPARTAN-I enhancements are what renders him immune to Flood infestation.
John-117, the Master Chief, the main protagonist of the franchise, is a SPARTAN-II, often referred to as "the last SPARTAN", though several other SPARTAN-IIs survive in the novel series. Halo Wars, taking place before the SPARTAN numbers were whittled down so drastically, allowed Human players to field SPARTAN-II infantry in their armies, though reflecting their limited numbers, only three supersoldiers per player can be active at one time. Halo Wars doesn't accurately reflect canon, however as the Spartans in the game have energy shields, while the game takes place before that technology should be available.
Halo: Reach follows a group of SPARTAN-IIIs called Noble Team, with the playable character, SPARTAN-312, aka "Noble Six", being their latest member. In order to make the gameplay more relatable to the player, even though Noble Team consists primarily of SPARTAN-IIIs (although one member, Jorge-052, is a SPARTAN-II), they have been specially issued MJOLNIR power armour to improve survivability.
Finally, while the Master Chief returns as the playable character in the primary campaign of Halo 4, he encounters the new generation of SPARTAN-IVs, lead by Commander Sarah Palmer, when he meets up with the UNSC Infinity on the Forerunner shield world Requiem. Players are cast as SPARTAN-IVs themselves in the game's multiplayer modes, the competitive "War Games", which are described in-universe as being combat training missions with SPARTANs competing non-lethally against each other, and the co-operative "Spartan Ops", which depicts the players' personalized SPARTAN-IVs as the members of Fireteam Crimson, carrying out new objectives on Requiem, and taking place six months after the end of the singleplayer campaign.