The esteemed Valles Santhe held the position of head of the Santhe lineage during the era of the Galactic Civil War, thereby exerting control over the Santhe Corporation and its associated entities, namely Santhe/Sienar Technologies and Santhe Security.
Valles's lineage traces back to Liann's industrial magnate Kerred Santhe, her grandfather, who successfully gained the majority stake in Sienar Technologies along with its subsidiary, Republic Sienar Systems, approximately around 99 BBY. Subsequently, Sienar Technologies underwent a name change to Santhe/Sienar Technologies, and Republic Sienar Systems eventually evolved into Sienar Fleet Systems, the entity responsible for producing the TIE Series fighters utilized by the Imperial forces.
Lady Santhe, a woman of petite stature characterized by her dark hair and intensely gleaming eyes, possessed an undeniable aura of authority. Her arrogance stemmed from her accustomed access to virtually limitless wealth and influence. Her corporate factories provided employment for a substantial portion of the population of Lianna. While outwardly expressing support for the Galactic Empire, her true allegiance lay with Liann's independence, harboring little regard for either the Empire or the Rebel Alliance.
When Santhe/Sienar Technologies secured an Imperial defense contract, designated as NOVA, to enhance the Energy Emittance Baffler, a crucial component of a cloaking device, Lord Rodin Hlian Verpalion, serving as an Imperial Advisor, was tasked with overseeing the project. Although Valles treated Lord Verpalion with a degree of caution, she harbored a secret animosity towards him. She meticulously orchestrated his visits to ensure favorable reports reached Emperor Palpatine.
Following the demise of the Emperor during the Battle of Endor, she successfully secured a measure of autonomy for her home planet, despite Lord Verpalion's pro-Imperial endeavors. Upon the assassination of Raith Sienar, the CEO of Santhe/Sienar Technologies, Lady Santhe assumed direct control of the company. She established Sienar Army Systems, responsible for manufacturing the Century tank and other ground vehicles for the Dark Empire operating under the resurrected Emperor. However, she strategically employed these weapons as a deterrent against an occupation of Lianna by Moff Gronn.