Scale of Tau Campaign

This book describes the Damocles War Zone and the battles that were fought there between a Tau Empire invasion force led by Commander Shadowsun and a coalition of Imperial forces that included Imperial Guard regiments, Imperial Knights, and Space Marines from the White Scars nad Raven Guard Chapters. The campaign was fought across a vast area that encompassed several Imperial sectors and dozens of Imperial planet. Initially the forces of Mankind were hard-pressed to halt or even slow the Tau onslaught. It was only wiht the arrival of contingents of Imperial Knights from House Terryn and Space Marines from the White Scars Chapter that the tide began to turn, and even these mighty warriors were unable to save the lynchpin hive world of Agrellan from being overrun.
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Echoing their Second Sphere Expansion more than two centuries earlier, the Tau Empire surged into Imperial space on a sector-wide front. They offered mercy to worlds that welcomed the teachings of the Greater Good, but a swift death to those that opposed them.
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The Imperium, despite its impossibly numerous armies, was ill-prepared to deal with the suddenness and strength of the Tau invasion. Many of the Imperial forces once stationed to defend the Damocles Gulf had been withdrawn to fight another, more pressing, threat in the form of an encroaching Tyranid hive fleet. In this manner, the Tau offensive could not have been better timed and they made swift progress deep into Imperial space. The Imperium's remaining armies were forced to retreat to their garrison worlds and fortify them as best they could. The rapidity of the Tau advance was abetted by many Imperial worlds that were sympathetic for the Tau's beliefs, the legacy of Water caste diplomants who had long been preparing the way for the Third Sphere Expansion.

Warzone: Damocles