Codex: Eye of Terror (2003), p7

Like so many sector-wide conflicts, the Gothic war began slowly, with sporadic, and seemingly insignificant raids against smaller outposts (qv. The Arx Raid). Vessels stricken with disease were discovered adrift in the Athena Sector, along with sightings of the Chaos vessel Plagueclaw, and Astropaths began reporting unsettling disturbances in the Warp. Panic and anarchy became widespread as fanatical sects arose, believing that the Emperor, bless his holy name, was displeased with them. Hysteria spread throughout the sector and on many worlds order broke down completely. The Imperial Navy lost several ships to 'accidents' in space dock that were subsequently blamed on poor maintenance and faulty ammunition - a rather too convenient explanation for my tastes. Three years after the first raid at Arx, the forces of the Despoiler struck.