Where the Force was first discovered.

From: Official Holonet Database

Mystical scholars gathered on the harsh and mysterious world of Tython millennia ago to begin the first studies of the Force, but controversy among the scholars’ ranks created a cataclysm which nearly destroyed the planet. A small group of survivors fled to another star system, put their dark past behind them, and founded the Jedi Order.

Thousands of years passed, and the true legacy of Tython was forgotten.

Rediscovering the planet early in the Great War, the modern Jedi began exploring the mysteries of Tython’s history, and learning much about the earliest Force users.

When the Empire sacked Coruscant and destroyed their long-standing Temple, the Jedi Council chose to rebuild the Temple on Tython and train a new generation of Jedi to battle the Sith menace. They soon discovered, however, that Tython’s mystical power carried its own dark legacy, a pervasive taint of unknown origins…