Taetrus is a turian colony in the Mactare system. In 2185, Taetrus fell into crisis when a turian separatist group known as Facinus reprogrammed the FTL plotter of a starship and rammed the ship at near-FTL speeds into the heart of Vallum, the colony's capital city, killing tens of thousands of people. This terrorist attack prompted the Turian Hierarchy and Taetrian colonialist forces to invade Facinus' strongholds and systematically eliminate the separatists in a short, decisive conflict called the War on Taetrus.