Altarrn, the original planet of the uncommon spidery nightgliders, existed in the Altarrn system of the Glythe sector, and was classified as a planet.
Sometime between 3000 BBY and 1000 BBY, Altarrn was found. The world was situated within the area controlled by the Galactic Republic, and later, the Galactic Empire. After the Empire's collapse, Grand Admiral Mitth'raw'nuruodo initiated the campaign against the New Republic, which then involved the planet. Following Thrawn's loss, the planet was taken by the Republic and later the Imperial Remnant. By 137 ABY, Darth Krayt's Empire had control over the world.