Early in the 24th century, Turkana IV was a Federation colony. Around 2330, the local government disintegrated and the planet fell victim to a civil war between the Coalition and the Alliance, two factions which had been given emergency powers by the crumbling government. The colony descended into anarchy and formally declared itself independent around 2350.
In 2361, the USS Potemkin visited the planet. The crew was informed that any attempt to set foot on the surface would be met with lethal force.
By 2367, the planet's surface had become an uninhabitable wasteland littered with ruins. The surviving residents had retreated underground, living in dilapidated underground complexes. Despite chronic food and supply shortages, both factions continued their civil war.
Frequent questions have been raised over the Federation's treatment of the Turkana colony. Considering the tenuous legitimacy of the warring factions and the abysmal living conditions on the surface, it remains unclear why only token attempts have been made at investigating or mitigating the Turkana situation. As a former Federation colony populated primarily (if not entirely) by humans, intervention on Turkana IV would not be prevented by the Prime Directive.