Event · M42

Fifth Sphere Expansion

The Fifth Sphere Expansion, also called the Fifth Sphere of Expansion, was a T’au Empire campaign of expansion led by Commander Shadowsun and launched from the Nem’yar Atoll after the Great Rift’s creation, when contact was made with Commander Surestrike and the remnants of the Fourth Sphere of Expansion through the Startide Nexus, a stable warp passage. When Shadowsun’s forces emerged from the Nexus they were welcomed into the Nem’yar Atoll, integrated the Fourth Sphere survivors, and began to enlarge that domain. Expansion was checked several months later by a Death Guard armada moving on the Nexus, an assault answered in the Battle of the Startide Nexus. The Sphere also fought Orks of the Ful’na Nebulae and scattered Tyranid remnants, and pressed into Imperial space while the Imperium was distracted by the aftermath of the Great Rift. Fourth Sphere commanders pursued neighbouring Imperial worlds with a violence unusual among the T’au, including massacres of prisoners and the sacrifice of auxiliaries; the Massacre of the Dul’un Lakes and the Eight Days of Infamy are the best-known of those episodes. Shadowsun and the Ethereal Council disciplined those commanders, among them Tash’var Shi Kais, with the ritual punishment called the Malk’la, and after a Kroot uprising on the colony of Ky’san all auxiliaries were removed from Fourth Sphere contingents. Despite that controversy the Sphere continued at pace, occupying several planets within months and opening warzones in the Chalnath Expanse and on Haephos, Astorgius, Riatov and Vorotheion. Late in the campaign Shadowsun and the Ethereal El’Vesh issued the Kesh’val Declaration, a clandestine order to send stealth flotillas against Necron tomb worlds for the Earth caste. The Battle of the Startide Nexus mauled the Fifth Sphere fleet and slowed its advance, and a Sixth Sphere of Expansion is already being planned.

See where Fifth Sphere Expansion occurred on the galactic map in the 41st Millennium.

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