Event · M41

Damocles Crusade

The Damocles Crusade was an Imperial campaign against the T’au Empire in the Damocles Gulf, fought between 742 and 745.M41. The war originated in the T’au Empire’s Second Sphere Expansion, during which Water Caste diplomats established trade agreements with frontier worlds of the Imperium along the Eastern Fringe. Alarmed by the resulting spread of alien goods, technology, and, in some cases, outright secession from Imperial rule, the Ultima Segmentum Command and the Inquisition sanctioned a punitive crusade. Its forces were drawn chiefly from the Astra Militarum, including regiments raised on Brimlock, together with several Space Marine Chapters, among them the Ultramarines, and elements of the Imperial Navy. Crusade forces crossed the Damocles Gulf and fought their way through the Hydass, Sy’l’kell, and Viss’el systems before reaching Dal’yth, a First Sphere sept world developed by the T’au as a showpiece colony of hex-cities and Water Caste markets. Fighting on Dal’yth proved far heavier than expected: T’au orbital defences, Kroot auxiliaries, and battlesuit infantry inflicted severe damage on the world’s hex-cities and stalled the Imperial advance around the woodlands of Gel’byrn. Towards the close of the crusade, the Scar Lords, a Space Marine Chapter, struck at Vior’los to avenge an earlier humiliation inflicted upon them by Commander Farsight on Dal’yth. The world was brutally occupied, and the Ethereals, the T’au ruling caste, were content to abandon it despite Farsight’s objections; with minimal aid from his closest followers, Farsight liberated Vior’los and destroyed the Scar Lords, at great cost to the world. Facing a costly stalemate on Dal’yth and the approach of the Tyranid Hive Fleet Behemoth, Imperial commanders accepted a negotiated withdrawal offered by the T’au Water Caste, ending the crusade without a decisive victor. In its aftermath, the Inquisition purged Imperial worlds suspected of collaboration with the T’au, while Dal’yth’s damaged hex-cities were gradually rebuilt through renewed trade; the world remains a commercial centre, and Gel’byrn continues to host alien embassies. Later T’au tradition, associated with the Ethereal Aun’va, came to interpret the entire crusade as a deliberately staged Kauyon, drawing the Imperium into a trap before revealing the true scale of the T’au Empire. The frontier fighting of the crusade, including the service of Brimlock’s regiments, and Farsight’s subsequent campaign toward Arthas Moloch both grew directly out of the Damocles Gulf war, while the later Taros Campaign renewed open conflict between the Imperium and the T’au Empire in the same region of the Eastern Fringe. Accounts of the T’au order of battle during the crusade differ regarding Commander Shadowsun. One account lists her among the commanders of the Fire caste (the T’au warrior caste), at the head of cadres fighting by the Kauyon (the “patient hunter” doctrine of ambush), alongside Commander Farsight, who led cadres fighting by the Mont’ka (the “killing blow” doctrine of the decisive strike), and Commander Bravestorm with the Defenders of Dal’ryu. Other accounts hold instead that Shadowsun had been placed in cryogenic stasis by the Ethereal Supreme Aun’va and was revived only during the Great War of Confederation, begun in 975.M41, after which she was chosen to succeed the rogue Farsight. The accounts are not reconciled. Among the Ultramarines who served in the crusade was Cato Sicarius, then an Assault Sergeant of the 8th Company, who fought beside his fellow sergeant Jorus Numitor. Sicarius showed a cold and ruthless violence in the campaign, executing Imperial Guardsmen who retreated before the T’au. The two Assault Marines came close to killing Commander Farsight in combat, and Farsight pledged revenge against them. After the 8th Company’s Captain, Ledo Atheus, was killed during the campaign, Numitor was raised to its command.

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