First Sphere of Expansion
The First Sphere of Expansion, also known as the Great Expansion, was the initial expansion of the T'au Empire from their homeworld of T'au and was a period of unprecedented growth for the Empire. It lasted from 502.M37 to 956.M38.[1a][1b]
Overview
The First Sphere of Expansion was launched from the planet T'au and lasted roughly a millennium for the T'au. It saw seven additional fully settled Septs: Tau'n, D'yanoi, Bork'an, Dal'yth, Fal'shia, Vior'la, and Sa'cea. The Poctroon were the first race to join the T'au Empire during this period, though they were later wiped out by disease. Later, the Nicassar became the first race to join and endure. The T'au encountered the Orks for the first time during this period[1b] and tried to negotiate with them but after the massacre of the delegates on Kor'voss and Vaslan Prime[2b], the Water Caste abandoned these attempts and T'au fought with the greenskins thereafter.[2a] The situation changed in favour of the T'au only after the Campaign of Cleansing.[1b] Also at this period the Thraxian race was assimilated.[2a] This was a terrific period of T'au growth that saw a massive population boom and unprecedented growth. The phase only came to an end because sparse T'au numbers could not keep up with their rapid advance and due to the sheer distance between systems that made crossing the span of the Empire impossible in a single lifetime. At the end of the Second Sphere of Expansion, the T'au encountered the Kroot, which eventually led to the T'au war effort to liberate them from the Orks in what culminated in the War in the Place of Union. For the next ten years, the T'au helped the Kroot drive the Orks from their worlds, eventually liberating their homeworld of Pech at the behest of the greatest Kroot leader Anghkor Prok.[1a]
During the intermission between the First and Second Spheres of Expansion, the Anthrazods and Brachyura were integrated into the Empire and helped prepare the T'au for the next war. However, the key to further T'au expansion came from the Sept of Fal'shia, where they finalised development of the ZFR Horizon Accelerator Engine. This finally allowed the T'au to attain near-light speed travel and launch the Second Sphere of Expansion.[1a]
