Old Republic, New Frontier
The infamous warrior tribes of the galaxy, that 300 years ago almost brought all of the Galactic Republic under its yield. Encouraged in secret by the Sith, and fought by Revan, Malak, and the others in the Jedi Order, they would quickly be decimated.
While not in their former state of glory, the Mandalorians are once again bringing themselves to power and notice in the Galaxy. While they had in the past tried to help the Republic, as moved by Mandalore Preserver, the new leader, often called Mandalore the False has been bringing back old sentiments against the Republic. While there are no invasions as of yet, the clans are gathering weapons, tools, and perssonel in rapid number.