This Datacron unlocks the codex entry - Galactic History 26: Naga Sadow's Deception
This datacron holds unheard of power and knowledge collected by an ancient race. You access its power and discover writings which are clearly only one small piece of a massive galactic history:
For years, the Sith Lord Naga Sadow had been arguing unsuccessfully that the Sith Empire needed to expand. His chance came when Gav and Jori Daragon, two hyperspace explorers, accidentally discovered Korriban. With the Daragons sentenced to death, Sadow helped them escape, planning to use them to rediscover the hyperspace routes to the Republic. He then claimed to the Sith Council that Republic agents had freed the prisoners. Surely invasion was imminent?
Naga Sadow's rival, Ludo Kressh, grew suspicious. As Sadow began to train Gav Daragon as his protege, Kressh raised a force against Sadow, hoping to expose his treachery. But Sadow crushed Kressh's armies and declared himself Dark Lord of the Sith. In the confusion of the battle, Jori Daragon fled back to the Republic, not realizing her ship carried a homing beacon for the Sith to follow.
Coordinates X -363, -147
This is probably by far the easiest Datacron to find on Taris mainly because it requires absolutely no special tactics or strategy to get to. This Datacron is located behind a stack of boxes in the Dynamet General Hospital in The Sinking City. The entrance to this hospital is around X -448, Y -161 (Screenshots 1 & 2). Head down into the entrance of the hospital and down each ramp until you come out to a large room (Screenshot 3). In the right corner ahead of you when you enter the room you'll see a large pile of boxes, I'm looking at this pile of boxes in Screenshot 3.
Run over to these boxes and hop on top of them, behind them you'll see a very well hidden tunnel (Screenshot 4). From here it's easy, all you want to do is follow the corridor all the way around until you reach the Datacron.