Voss Civil War

"'The Voss have been consumed by a devastating civil war, I think the sith are behind it.' Jedi General Ram Kota to the Jedi council and Republic senate"The Voss Civil War (22 -19 BBY) was a proxy war fought under the shadow of the much larger and devastating conflict known as the Clone Wars. The war was fought between the Voss Ascendancy and the Brotherhood of Chaos a rogue militant extremist group of Voss mystics that favored the Dark side of the Force, and sought to conquer the galaxy. The war was mainly fought in Voss space but spilled into the Mid and Outer Rim and forced the Republic to intervene.

In Secret the Brotherhood of Chaos were supported by the Black Imperium, a sith military Junta in the unknown regions who follow the Order of the One sith. Then the "Diseased" a group of Undead created by the Black Imperium unholy experiments during the 3rd Sith Civil War (3632 BBY - 3630 BBY), launched an attack causing a temporarily truce between the opposing sides.

With the Diseased defeated and driven from Voss space, the war continued up until the end of the clone war, with the Voss Ascendancy defeating the Brotherhood of Chaos, and ending the war.

Split between expansionists and Isolationists
The Voss Ascendancy was divided between the aggressively militaristic expansionists, who wanted to expand their power and strike at potential threats such as the Confederacy of Independent systems, and the Republic, and the less aggressive but equally as militaristic Isolationists, who wanted a strong military to defend themselves from attack, but not get involved with other fractions wars, or political issues. They saw the Clone war as an internal debate and the Republic and CIS shouldn't involve other fractions, as it was basically just a glorified civil war.

The divide grew larger and larger, as the Republic and CIS tried to convince the Voss to join the war. The Confederacy of Independent systems even tried an invasion and staged a fake Republic invasion of Voss colonies within Republic space, but were thwarted by the Voss Mystics who foretold of the trickery and invasion. The Republic also tried to force the Voss to Join, the Jedi attempted to kidnap a group of Voss initiates visiting Naboo but were thwarted once again when the Voss Mystics foretold the kidnapping and hired the Mandalorian Watchmen lead by Countess Miko Tula to protect the Initiates.

Even the Voss Mystics were divided some wanted to gain ultimate power, but didn't trust the Jedi and sought after the teachings of the Sith particular the First Grey Sith Lord Darth Ulrigiga. Others supported the Isolationists, in 24 BBY a armed Coup occurred and was quickly put down.

Influence of the Black Imperium
The Black Imperium taking advantage of the growing divide between the political fractions within the Voss Ascendancy and their distrust of the Jedi, Republic, and Confederacy of Independent Systems. They began to sow the seeds of distrust and reached out to the Mystics and political and military leaders who wanted to expand and promised them power, and strength, and began to supply weapons, and equipment to them. They also interfered with and weakened the power of the current Prime Minister Nal-Ko and her cabinet, soon Civil war would be inadvertent.