League of the Six Kingdoms

The League of the Six Kingdoms was a union of six Rakatan warlord empires that spanned the entire length of the eastern galaxy, from 80,092 BBY until 49,814 BBY, when it was dissolved by the Celestials and Khoboka. At the head of each of the six constituent kingdoms was a powerful warlord known as the Barraki, a title passed down via primogeniture for many generations. 
Due to the limits of Rakatan hyperdrive technology, the Barraki only controlled a limited number of worlds despite the vast theoretical size of their realm. The League controlled the eastern side of the Galaxy, the other side being controlled by the Dominion of the Celestials .
The last and most famous generation of Barraki attempted a rebellion against the Celestials in 49,820 BBY. When this failed, the League of the Six Kingdoms was dissolved (to eventually—more than 15 millenia later—be repalced by the Rakatan Infinite Empire). The rebellious Barraki were teleported to the depths of the ocean world Ghalon Mahri by Alkaadi.