T'au Empire Lore: The Greater Good, the Castes, the Ethereals, Shadowsun and Farsight (Plus How to Start an Army)

The T'au are the youngest empire in the galaxy, and the most hopeful. In just a few thousand years they went from stone tools to starships and battlesuits, united under a philosophy called the Greater Good. But behind the optimism lie secrets, rebels and questions about who really pulls the strings.

Army guide, last updated November 4, 2026. Lore summarised in our own words from Black Library novels, codexes and community wikis. For game rules, use the official codex or the official app.

The T'au in 30 seconds

A sudden rise

Only around six thousand years ago, the T'au were primitive tribes on their home world, T'au. Their warring castes, the plains hunters, the city builders and the sky-dwellers, were close to destroying each other when strange figures appeared: the Ethereals. They spoke of a Greater Good, and the fighting stopped. From that moment, T'au progress accelerated at an astonishing pace.

The castes

T'au society is divided into five castes, each with a role:

• Fire caste: the warriors and soldiers.
• Earth caste: engineers, scientists and builders.
• Air caste: pilots and space travellers.
• Water caste: diplomats, merchants and negotiators.
• Ethereal caste: the leaders, who hold everything together.

The Ethereals' influence over other T'au is almost unnatural. Some in the Imperium suspect they use pheromones or psychic tricks; the truth has never been confirmed.

The Greater Good and its allies

The T'au welcome other races into their empire, as long as they accept the Greater Good. Their armies include the bird-like Kroot, mercenary hunters who evolve by eating their prey, the insectoid Vespid, and even human worlds of the Imperium that chose to join them, the Gue'vesa.

Expanding across the stars

The T'au expand in great waves called Spheres of Expansion. During the Damocles Gulf Crusade, the Imperium attacked them for the first time and failed to crush them, a shock to humanity. Since then, the T'au have fought the Imperium, Orks and Tyranids, growing larger with every war.

Farsight: the rebel commander

The T'au's greatest hero, Commander Farsight, was sent to fight the Orks beyond the borders. During his campaign he found an ancient sword, the Dawn Blade, and discovered something that made him lose faith in the Ethereals. He broke away and founded the Farsight Enclaves, a group of worlds that follow the Greater Good without the Ethereals. Farsight is still alive, centuries later, which is a mystery in itself.

Shadowsun and the Fourth Sphere

Farsight's great rival is Commander Shadowsun, the T'au Empire's supreme military leader. She led the Fourth Sphere Expansion, which was swallowed by a warp disaster and lost for years before returning changed. Today the T'au face the chaos of the Great Rift, as a young race in a galaxy that is suddenly far more dangerous.

Famous T'au

• Commander Shadowsun: the empire's greatest strategist.
• Commander Farsight: the rebel hero of the Enclaves.
• Aun'Va: the Ethereal Supreme.
• Darkstrider: a Pathfinder who thinks like his enemies.

Black Library books to read

• Farsight: Crisis of Faith (Phil Kelly): Farsight's break with the Empire
• Fire Caste (Peter Fehervari): the T'au and humans in a dark war

We may earn a commission from links on this page.

Find them as Black Library paperbacks and audiobooks.

Collecting T'au: a quick guide

T'au want to stay at range and shoot: battlesuits, Fire Warriors and drones. They're weak in close combat. Start with: a T'au Empire Combat Patrol.

Painting tip

Smooth, panelled armour is great for practising clean edge highlights. A paints and tools set covers the basics.

New to the hobby? Start with our Warhammer beginner's hub, and see the other army guides.