Oriana was a planet located somewhere in the space of the galaxy's Alpha or Beta Quadrants. It was the homeworld of the Orianian civilization.
History and specifics[]
The Orianians were divided into three mutually hostile factions: the Venturi, the Torlick, and the Green. Some time in the 22nd century, the Venturies and Torlicks began a destructive war that lasted for two centuries. By the mid-24th century, this war had left the world devastated and badly polluted, with little remaining surface vegetation, a barely breathable atmosphere, and the Orianian people sickly and slowly dying out. (TNG novel: Nightshade)
Oriana had some links with Orions. In the year 2359, after Orion pirates attacked the Federation starshipUSS Starbound, Starfleet Commander Darryl Adin was accused of colluding with them, in exchange for a large payment to numbered bank accounts on Oriana. (TNG novel: Survivors)
By the late 2360s decade, the Venturies and Torlicks began peace negotiation and the Starfleet starship USS Enterprise-D was sent to assist. Captain Jean-Luc Picard, Lieutenant Worf and Counselor Deanna Troi visited Oriana, and became caught up in conflicts there. Finally, with all three sides dedicated to the peace process and restoring their world, Oriana awaited a permanent Federation advisor. (TNG novel: Nightshade)