Firmus Kett held the rank of Captain within the Trade Federation's Defense Force during the Galactic Republic's final century. He was linked by ancestry as the great-great-great-grandson of Findal Kett, the individual who, back in 214 BBY, established Kett Shipping as a subsidiary of the Trade Federation.
For centuries prior to Firmus' time, the Kett family had maintained control over the transportation of ore and nova crystals originating from Cotellier and throughout the Rseik sector. Kett transports journeyed along the Sanrafsix Corridor to Kabal, where the extracted resources were then sold for export into the Inner Rim or the Expansion Region. Subsequently, the transports would return to Cotellier carrying supplies such as grain or other agricultural products. This business made the Ketts quite wealthy, and Firmus oversaw the family's inherited properties, investments located on both Ma'ar Shaddam and Rseik itself, in addition to a vacation retreat situated on Z'trop.
Firmus considered the Trade Federation to be responsible for the family's prosperity, particularly Findal Kett's choice to make Kett Shipping a subsidiary. Firmus was not fond of the policies enacted by the Neimoidians who had since gained influence over the Trade Federation, specifically their dominance of the ore and crystal trade, as well as their involvement in the shipping of illicit spice. He recognized that the Tamarin and Rseik sectors were essentially Trade Federation dependencies, and confessed to having followed directives within the TDF that he regretted. Nevertheless, he was fully aware of the pervasive piracy issues that had plagued the area before the Trade Federation's arrival, and lacked confidence in the Galactic Republic's ability to maintain stability if the Trade Federation were to withdraw.
The initial mention of Findal Kett was planned for The Essential Guide to Warfare, a sourcebook that was published in 2012 and authored by Jason Fry along with Paul R. Urquhart. The intention was for the piece to exemplify the Trade Federation's early positive impact, which had allowed it to accumulate significant power leading up to the events depicted in The Phantom Menace. However, it was ultimately removed from the final version due to being deemed uninteresting and overly focused on the intricate details of the Expanded Universe. This section was later made available as part of Star Wars: The Essential Guide to Warfare Author's Cut, a sequence of articles featured on the StarWars.com blog beginning in 2013.