The son of Separatist Senator Mina Bonteri, Lux was young, idealistic, and skeptical of the aims of the Republic and the Jedi Knights. His father was a fervent supporter of the Separatists, and was killed by clone troopers on Aargonar. Lux did not know what to make of Ahsoka Tano and her visit to Separatist space. After a failed peace overture begun by Mina extended to the Republic, Lux's mother died under mysterious circumstances attributed to the Republic. Lux filled her position in the Separatist Senate, representing his home planet of Onderon.
Lux's mother was a Senator in the Confederate parliament on Raxus. She believed that a peaceful end to the Clone Wars was possible through diplomacy.
Lux was the first non-combatant Separatist that Ahsoka Tano truly got to know. Likewise, Ahsoka was the first Jedi that Lux had ever met. Their time together helped reshape their ideas of what was formerly a faceless enemy.
When Lux discovered that it was Count Dooku who ordered his mother's death, he swore to bring the Separatist leader to justice. At a peace conference at Mandalore, Lux loudly accused Dooku of murder, drawing the former Jedi's deadly attention.
Lux knew that he and Death Watch had the same aims: revenge against Count Dooku. Lux badly misjudged the character of the Mandalorian mercenaries and underestimated their capacity for cruelty.
Returning to Onderon after an ill-fated attempt at a vendetta against Count Dooku, Lux joined the rebel cause, hoping to secure legitimacy for the insurgents and establishing a secret alliance with the Galactic Republic through his contacts with the Jedi.