A T’au Sept is a star system, or group of star systems, that belongs to the Tau Empire. Each one is named after its capital world and run by its own Elemental Council, which is why Tau from different septs can feel like they come from different countries.
What a sept actually is
Think of a sept as a province with its own planets, moons, orbital stations and void structures. It takes its name from the sept world at its centre, sometimes called the prime or capital planet, and that world is where the local government sits.
Every sept gets its own symbol and colour scheme. Those markings show up on armour and vehicles, and they usually reflect whatever the sept is known for, so you can often guess a Fire Warrior’s homeworld just by looking at their shoulder pad.
- Named after its capital world
- Own symbol and colour for markings
- Includes every world, moon and station in the system
Who runs a sept
Each sept is managed by an Elemental Council. It has seats for all five castes (Ethereal, Fire, Air, Water and Earth), plus a sixth observer seat handed to a prominent member of an auxiliary race for an outside perspective.
That sixth seat is advisory only. The Ethereal representative always gets the final word, which keeps the caste system firmly in charge.
The septs by expansion sphere
New septs get founded during the Tau’s Spheres of Expansion, and a sept’s prestige is often judged against the other septs founded in the same wave. The homeworld and the First Sphere septs form the core of the empire.
Later spheres pushed further out. The Second Sphere ended when the Tau crossed the Damocles Gulf and ran into the Imperium, and the Third and Fifth Sphere septs came after. Some septs don’t fit neatly into any sphere at all.
| Sept | Sphere | Known for |
|---|---|---|
| T’au | Homeworld | Capital and cultural centre; its people are seen as learned and wise |
| T’au’n | First | First offworld colony; pioneers |
| Bork’an | First | Learning and academia |
| D’yanoi | First | Long isolation; seen as rustic and backwards |
| Dal’yth | First | Cosmopolitan and trader-friendly |
| Fal’shia | First | Technology and problem solving |
| Sa’cea | First | Disciplined, honourable Fire Warriors |
| Vior’la | First | Aggressive, highly skilled Fire Warriors |
| Au’taal | Second | Beautiful world; easygoing citizens |
| Elsy’eir | Second | Poetry and art; creative intellectuals |
| Ke’lshan | Second | Repeated raids by alien races |
Why septs matter on the tabletop and in lore
Sept choice is the Tau equivalent of a Space Marine chapter. It gives your army a identity, a colour scheme and, in the rules, a set of traits that push you toward a particular playstyle.
In the lore, sept culture shapes characters too. A Vior’la commander and a Dal’yth diplomat come from the same empire but won’t think alike, and that friction is part of what makes Tau stories interesting.
Key facts
- A sept is a star system or group of star systems within the Tau Empire, named after its capital world.
- Each sept has its own symbol and colour scheme used on armour and vehicles.
- Septs are governed by an Elemental Council with seats for all five castes plus one auxiliary observer.
- The Ethereal representative on the council holds the final say.
- Septs are founded during Spheres of Expansion and grouped by which sphere they belong to.
- T’au is the homeworld and the empire’s capital; the First Sphere septs form the empire’s core.
FAQ
What is the difference between a sept and a sphere of expansion?
A sept is a place, a star system or group of systems. A sphere of expansion is a period of colonisation. Most septs get founded during one sphere, which is why septs are often grouped by sphere.
What is the most important T’au sept?
T’au itself. It’s the homeworld and the political, cultural and administrative heart of the empire, and its citizens are regarded as especially learned.
Do all septs have their own rules?
In the game, each playable sept gets its own traits and warlord options. The exact list changes between editions, so check your current codex.