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Tau Warrior[4a]

The Tau are a young race of technologically-oriented beings from the Eastern Fringe and the dominant species of the Tau Empire. T'au, the Tau home planet, was discovered in 789.M35 by the Adeptus Mechanicus Explorator Fleet ship Land's Vision. Adeptus Mechanicus records indicate that at that time, the Tau species had mastered the use of simple tools and weapons, as well as fire. Before the planet could be cleansed and colonized by the Imperium, however, a violent Warp-storm erupted around the planet. The outbreak of the wars of the Age of Apostasy shortly thereafter preempted any further Imperial follow-up and the then-minor xenos race was effectively forgotten by humanity outside a few Explorator records.[10a]

It would be another six-thousand years before the Imperium had any further contact with the Tau, when an unknown class of alien vessel was encountered by system defense ships at Devlan in the Ultima Segmentum. After failing to respond to naval challenges, the ship was opened fire on and destroyed. Bodies recovered from the wreckage were a close match to the records from the Land's Vision. The rapid elevation from a primitive species on a single planet to a starfaring power in only six millennia represented a new danger to Imperial interests, especially as some of the human worlds on the fringes of Imperial territory were discovered to already have trade relations with the Tau. Almost a century later, the Damocles Crusade smashed into Tau space, bringing the two powers into war.[10c]


Early Tau History

The Tau Empire

The primitive Tau were a plains-dwelling race. In their prehistory, they lived as nomadic tribes on the desert plains, hunting and gathering their food. Some of these tribes eventually expanded into other environments. The Tau of the mountains grew flaps of skin and light bones that allowed them to float over the deserts on thermal drafts. The Tau of the river valleys developed agriculture and metallurgy, forming the first true settlements. The development of settlements led to the need of trade, and wandering Tau began to negotiate and mediate between the disparate tribes, traveling up and down rivers in crude barges. The Tau that remained on the plains became strong and skillful hunters, larger and stronger than most other Tau.[10b]

Unfortunately for the Tau, the rapid sociological, biological, and technological shifts they were undergoing lead to conflict. The mountain Tau and the plains Tau allied to take the farms and cities of the river valley Tau, and the merchant caravans were regularly sacked to prevent alliances from forming. The Tau of the river valleys leveraged their skill at architecture to build walls and fortresses, and quickly discovered the manufacture of black powder weaponry to defend themselves. But with the harvests disrupted, the breakdown of trade, and blocked access to fresh water, disease ran rampant in the squalid conditions most Tau now lived in, and as many died from sickness as battle. Tau history records this period as Mont'au, "The Terror" or "death age".[10b][8f]

Tau legends tell of the first appearance of Ethereals at the besiged city of Fio'taun after the strange lights appeared in the skies.[8c] The fortress city of Fio'taun was under assault by the warriors from the plains. Though negotiation had been attempted, the fierce plain warriors would settle for nothing less than the annihilation of Fio'taun. For five long years, the inhabitants held off the savage assaults with their thick walls and plentiful cannons. However, disease and starvation began to take their toll. As the tide of the siege turned, two mysterious Tau appeared. One made his way into the camp of the plains Tau, exuding a quiet authority that no Tau was able to resist. Soon, the leader of the plains warriors was persuaded to parley with the Tau of Fio'taun. Similarly, the other mysterious Tau made his way deep into the fortress. Within a few short hours, the gates stood wide open, and the Tau stood ready to talk.[10b]

The two Ethereals spoke of the importance of peace and understanding between all Tau. They described a Greater Good that each Tau must strive towards. The besiegers and the besieged quickly agreed with the Ethereals and a truce was reached. Across the land, other Ethereals emerged, each with the same quiet authority and message of harmony and cooperation. Within a few years, the Ethereals had all of T'au working together.[10b]

Tau Empire Expansion in the Galaxy

Tau planets

First Sphere

This was a dynamic period that saw the Tau rapidly take from their homeworld T'au to the stars. Losses among the initial colonists were high, but under the protection of the Fire Caste the expansion continued undeterred. During this period the nascent Tau Empire assimilated their first alien cultures under guidance from the Ethereals, the Thraxians, the Nicassar, the Kroot, and several others. The Orks were a notable exception, the savage greenskins giving the Tau their first experience of full-scale inter-species war. By the end of this period, eight major Septs had been established.[11]

Second Sphere

Fueled by the newly discovered ZFR Horizon Accelerator Engine that allowed Tau ships to push out into further trips than they had previously been limited to, this period of Tau history is characterized by their first ventures across the Damocles Gulf. Several holdings were established on the far side, and several existent local powers were brought into the Tau's fold by conquest or trade agreement. Unfortunately for the Tau, this included worlds of the Imperium of Man, a galactic power the scale of whom the Tau were then-ignorant. The efforts of the Second Sphere Expansion were cut short when the Damocles Crusade quickly annihilated the Tau's holdings on the far side of the gulf and proceeded to penetrate deeply into the heart of Tau territory before being fought to a stalemate at Dal'yth Sept.[8e]

The Tau battle the forces of Nurgle

Third Sphere

The wake of the Imperial withdrawl from Tau space left the Empire on the brink of collapse as the enormity of what the Tau faced was made clear. The Ethereals, realizing that the Empire must quickly regain the initiative to bounce back from this loss, declared that this would be the catalyst for renewed vigor in their expansion efforts. Fleets of military conquest and colonial expansion, first lead by Commander O'Shovah and then later by Commander O'Shaserra, were dispatched to reclaim territory lost to the Tau, and they captured several Imperial worlds who had been stripped of their defenders to rally forces for the Battle for Macragge. Each conquest further built the Tau's strategic momentum.[10c][11]

Eventually, the Third Sphere of Expansion was ground to a halt due to Imperial counterattacks in the Damoclces Gulf and the formation of the Great Rift.[13]

Fourth Sphere

The Fourth Sphere of Expansion was launched shortly after the formation of the Great Rift. Utilizing new anti-matter engines, the fleet was thought lost in a mass accident but in truth was cast across much of the galaxy through a wormhole. Years after its disappearance, the Fourth Sphere was able to make contact with the Tau Empire through the wormhole, resulting in the Fifth Sphere of Expansion.[15]

Fifth Sphere

The Fifth Sphere of Expansion was launched on the heels of the ill-fated Fourth. It is the current phase of expansion of the Tau.[13] The expedition moved into the wormhole left behind by the Fourth Sphere, now known as Startide Nexus.[15]

Tau Society and Physiology

The broad role a Tau fulfills in their society is dictated by the caste to which they are born, and each caste is physically distinct from one another, to the point of being practically separate sub-species.[10f] The Tau of the Fire Caste are the warriors of Tau society, and are the most massive and physically powerful of the Tau, generations of breeding having weeded out infirmity. Tau of the Earth Caste have the most numerous population of all the castes, most being physically sturdy laborers who staff farms, factories, and construction crews, and their brightest minds go on to be engineers and doctors. Tau of the Water Caste are the civil servants, merchants, administrators, bureaucrats, and diplomats of Tau society, flowing among both the other castes and other allied species and ensuring that all have what they need to optimally serve the Greater Good. They display an easy affinity for languages, and adopt many forms of communications with exceptional nuance across their careers. Tau of the Air Caste are sometimes known as "the invisible caste" because they spend most of their time aboard the spacecraft that make up the Tau navy. Generations of exposure to micro-gravity leaves them with hollow bones and a tolerance for high acceleration, though their frailty means they are sluggish and weak in even moderate gravity environments. Finally, Tau of the Ethereal Caste are the spiritual and political leaders of the Tau, and Tau of other castes submit to their authority in all things. Should an Ethereal order a Tau of a different caste to kill themselves, they would be obeyed instantly and without question.[8f][10d]


The Tau are the most open and tolerant of the races in the galaxy, which means that they prefer not to destroy all other races on sight and are nowhere near as xenophobic as the Imperium. They are appreciative of the ways of the humans, Eldar, and other sentient races, but hold their own values as superior above all others.[Needs Citation]

All Tau in all castes have a particular rank in their society, with each individual starting at the lowest and being eventually promoted on merit. However, the Tau attach no stigma to low rank, and even the most menial Tau enjoys the respect of their peers.[12]

Tau Firewarrior

Tau names are generally seen in the Imperium as long, complicated, and unwieldy, but they can be broken down into the following:

  • Caste and rank within that caste.
  • Sept of birth.
  • Personal name (which is often determined/extended by their notable actions or achievements)

Using a Tau's full name is considered a very formal form of address, while using only their personal name is considered overly-familiar unless one is bonded to them via the Ta'lissera. Using a Tau's caste and rank to refer to them is considered a polite form of address as it acknowledges their roll in the Greater Good.[12]

Castes and Rank

The Caste System organizes all Tau into five different castes and each one of them has a defined social role, be it military, trade, diplomacy, or leadership. The members of a caste are further classified by a specific rank.[12]

Main article: Caste System

The castes are:

From lowest to highest, the ranks in Tau society are:[12]

  • Saal
  • La
  • Ui
  • Vre
  • El
  • O


Tau come from many planetary systems, or Septs, and these shape and define their methods of work. Some of these are:[12]

Personal Name

Tau personal names, unlike those of humans, usually mean things in their language, depending on the deeds in their lives. These names are apparently not assigned at birth, but descriptive of the individual as they distinguish themselves. Some examples are 'Kais' (Skillful), 'Vral' (Undercut), and 'Tsua'm' (Middle).[12]


Thus, the Tau named "Shas'O Vior'la Shovah Kais Mont'yr" (a.k.a. Commander Farsight) would be broken down as follows:

  • Shas - The individual is a member of the Fire Caste...
  • O - ...who is a high-ranking Commander and hero...
  • Vior'la - ...who comes from the Sept of Vior'la...

...and has a personal name translated as being far-sighted (Shovah), skilled (Kais), and having seen many battles (Mont'yr, meaning "blooded").[12]


Every Tau is humanoid in shape, with two arms, two cloven feet, and a single head. Their grey-blue skin is leathery and tough and exudes no moisture, owing to the generally dry conditions of their homeworld. Their faces are flat, wide around the eyes, and their olfactory organs are located inside their mouths. Their eyes can see into the infrared and ultraviolet. Tau eyesight is good, but they focus on distant objects slower than humans. The Tau are not very good in close combat, as they find the whole concept uncivilized.[Needs Citation]

The colour of a Tau’s skin often depends to his caste as well which sept he calls home. In general it can be said that the the Air caste have the palest pigmentation, while Fire caste tend to have the darker. The darker the Tau’s bluish-grey skin, the closer to the sun he lives - therefore those living on Vior’la have much darker skin than those from B’orkan. Also it is known that some strange quality in the green-tinged sun of the N'dras sept can leave those from that region slightly mottled.[4b]

It has also been suggested by several Imperial observers that Tau blood is bluish-purple, explaining that the blood contains trace amounts of cobalt, rather than iron as common in humans[5] (although this would actually result in an amber-yellow colour when oxygenated).[Needs Citation]

It is known that life span of the Tau is short.[7] Most tau need only 1-2 decs (1,5-3 Terra hours) of sleep per every rotaa (rotaa - 15 Terran hours), so approximaley 1,5 Terra hours for 15-hours Tau "day".[14]

Tau and the Warp

The Tau have no psykers whatsoever among their ranks, for their souls are so feeble they barely register in the Warp at all. They are largely oblivious to the malevolent forces of Chaos, who in turn take no interest in the crumbs that are Tau souls. No Tau has ever been corrupted by Chaos.[Needs Citation]

Because they have no Navigators, Tau ships cannot travel through the heart of the Warp like Imperium ships do. Instead, they make shallow "dives" into the Warp, a much slower form of travel. Because they have no astropaths, the Tau are reliant on messenger ships to communicate across the stars. These handicaps greatly slow the expansion of the Tau Empire.[Needs Citation]

Tau Warfare, Warriors, and Weapons

Tau Command Center[3]

Tau Warfare

Tau ground warfare is carried out almost exclusively by the Fire caste, while the Air caste is responsible for aerial and space combat, and providing transport between systems. The basic Fire Caste military unit is known as a Cadre, or Kau'ui[12], similar in size and role to an Imperial Guard Company, and is primarily made up of Tau from the same sept.[15]

The most commonly-fielded Cadre is a combined-arms formation (made up of multiple Teams, or La'rua), though more specialised Cadres exist such as a Battlesuit Retaliation Cadre and a Pathfinder Infiltration Cadre. Three to six Cadres will often fight together as part of a Contingent, or Tio've similar to an Imperial Guard Regiment and commanded by the most senior Cadre commander. Three to six Contingents may be grouped together into a Battle (also known as a Commune or Kavaal), though this is only a temporary formation. All Fire Caste forces in a given location, whether a planet or star system, is grouped into a Command under the leadership of a High Commander, with the four Commands (or Uash'o) (Fire, Earth, Water and Air) grouped into a Coalition (or Shan'al) under the command of the local Ethereals.[15]

The Tau prefer to carefully plan their assaults and tend to fight only after carefully coordinating all available troops. They also prefer to fight offensively, concerned more with the destruction of the enemy than the taking and holding of ground. The Tau believe that territory is much easier to hold when all enemies are dead. Instead of trying to defend a base or city, the Tau would rather dismantle all the important technology, evacuate, and come back to defeat the occupying force at a later time when their army is sufficient for the task.[Needs Citation]

The two primary Tau tactics are the Mont'ka (Killing Blow)[8a] and Kauyon (Patient Hunter).[8b] The Mont'ka is a carefully planned attack designed to wipe out critical enemy defenses or units in single, well-placed strikes. Once the strongest points of enemy resistance are crushed, the remainder of the force can generally be finished off more easily. Pathfinder Team or Ghostkeel make the final decision to launch a Mont’ka. After the beginning of the Mont’ka, the enemy must receive massive damage, or else the Tau forces will be called back – a Commander will withdraw to strike from another side rather than waste lives of the warriors.[8a] The Kauyon is essentially an ambush, where the enemy is drawn by use of a "lure" into a carefully prepared killing zones. The lure can literally be anything - from the allied squad to the vital object. The force of the Patient Hunter deployed in such a way that they can attack the enemy using all suitable advantages. True experts of this tactics may compose so many levels of plans within plans that the enemy realise that all of his actions have been predicted and managed by the Tau only at the annihilating ending of its battle.[8b]

The Tau have a formidable standing army but also make use of auxiliary units including the Kroot, Gue'vesa Auxiliaries, and Vespid, sometimes using them as the lure in the Kauyon attack method.[Needs Citation]

Space Fleet

The Tau space fleet is known as the Kor'vattra, and is crewed by Tau of the Air Caste. Since the earliest days of the First Sphere of Expansion the Kor'vattra was given high priority by the Ethereals, and their space-faring technology advanced at a rapid pace, increasing their reach substantially in the span of a few centuries. The Kor'vattra suffered tremendous losses to the Imperial fleet during the Damocles Crusade, with their defeat at the Hydass system being particularly noteworthy. Compounding the weaknesses were exploring tendrils of the Tyranid hive fleets encroaching on Tau space. Following this, the Ethereals directed the very best Earth Caste scientists were given whatever resources they needed to modernize and expand the Kor'vattra in a program titled the Kor'or'vesh. It is believed that the Tau's aggressive territorial expansion and the need to upgrade has placed great pressure on the Kor'vattra.[11]

Tau Warriors

The Tau are very much a ranged-combat oriented army. A common tactic is to engage the enemy at the maximum range of their weapons, which typically have a longer range and greater firepower than the equivalent weapons of other armies. Tau usually try to take out the strongest weapons of the enemy as well as keeping enemy troops from reaching the Tau lines, as most Tau units are weak in close combat. A more prevalent tactic amongst Tau veterans is the "Mecha-Tau" approach, which utilizes the inherent mobility and speed of Tau vehicles and battlesuits to confuse and overwhelm the enemy by engaging them at all levels of the battlefield.[Needs Citation]

The Tau army is highly specialized, with each element normally having a specific task in support of the rest of the force. Fire Warrior teams make up the line troops while forward scouts known as Pathfinders scout enemy positions and provide fire support with Rail Rifles and markerlight target designators. The Tau also deploy Broadside Battlesuits and Crisis Battlesuits in supporting roles, providing specialized weapons to deal with any hot spots on the battlefield or providing heavy anti-tank fire. Stealthsuit teams operate independently of the main force, unleashing devastating fire from hidden positions.[Needs Citation]

The Tau also make extensive use of small, A.I.-controlled drones, typically equipped with guns or forcefields. Drones can be used to protect teams of Fire Warriors and battlesuits or support tanks, and can even be grouped into independent squadrons.[Needs Citation]

Tau Weapons

Main article: Tau Armoury

The basic weapons of the Fire Caste propel particles that break down into plasma pulses as they are fired. This is commonly used in the long-range pulse rifle and more portable Pulse Carbine, the latter of which sports an underslung grenade launcher. A rapid-fire variation of the pulse carbine, known as the burst cannon, is also used on vehicles and battlesuits.[Needs Citation]

The Tau are known to use ion cannons and railguns in their ships as well as their vehicles with various guided and unguided missiles. They also arm their battlesuits with a variety of weapons, ranging from burst cannons and Missile Pods, to Fusion Blasters, Plasma Rifles, and flamers.[Needs Citation]

Other Notable Wars and Battles

Notable Characters


The Tau ally and hire various alien species, and employ them in their military as Auxiliaries.[Needs Citation]

Alien Races Assimilated and/or Destroyed by Tau



Background Information

In the dystopic Warhammer 40,000 universe, the Tau are the "least evil" race. They are more merciful, liberal, and progressive than the other races. They do not wish to exterminate other species, but integrate them into their empire. They have a thriving scientific tradition. Most importantly, they are not subject to the corrupting influence of Chaos, arguably the root cause of the tragic history of the humans and the Eldar. They were originally intended to be the "good guys" of the setting. However, fans felt the Tau were too likeable for the grim setting, so later editions introduced some darker aspects, such as the mind-control powers of the Ethereals and their habit of exterminating conquered populations that stubbornly refuse to integrate into the Greater Good.[Needs Citation]

See Also