The Veil War was a long war fought between the Tau Empire and Arachen. Beginning after the Arachen refused to join the Empire and instead drove the Tau from their territory, for years the Tau and Arachen battled for control over the Western Veil. However slowly but surely the Tau were able to get the upper hand, and in a final push by Vior'la warriors Commander Dawnstone led an offensive that finally broke the Arachen hold over the Veil. The final act in this plan was to have a Crisis Battlesuit team led by a young Commander Farsight assassinate the Arachen leadership, known as the Arachen Trinity. Farsight was successful, and now leaderless the Arachen were finally driven from the Western Veil.