Siward Cass Siward Cass was a Human male military officer who served the Galactic Empire aboard the first Death Star during the Galactic Civil War . By 0 BBY , he was a war veteran and had acted as an aide to Grand Moff Wilhuff Tarkin for many years . Biography . A Human male , Siward Cass was born in the Patriim system , within the Seswenna sector of the Outer Rim region of the galaxy . At some point during his life , he joined the ground forces of Palpatine ' s Galactic Empire . For many years , he served as an aide to Wilhuff Tarkin , Grand Moff of the Oversector Outer . By the time of the Galactic Civil War , a major galactic conflict fought between the Empire and the Rebel Alliance , he was considered a veteran . Cass acted as the chief communications officer aboard the first Death Star battlestation . He was entrusted with extremely sensitive information and communications between Tarkin and the Imperial government . Because of this , he was part of the Death Star command , and had a seat at its conference table . Cass ' duties ranged from handling routine communications to delivering priority news to the Grand Moff . In 0 BBY , the Imperials managed to capture Princess Leia Organa of Alderaan , who had strong ties with the Rebel Alliance , and Tarkin tried to make her confess the location of the Rebels ' headquarters . Organa ended up giving the name of Dantooine , after which that planet was checked for Rebel presence . Subsequently , Cass was committed with the delicate task of reporting to Tarkin that it no longer held any active base . Although he found the situation uncomfortable , Cass did his duty with no signs of nervousness . Having made his report , he immediately exited the room . Cass perished as the Death Star was destroyed during the Battle of Yavin . Personality and traits . Around the Battle of Yavin , Siward Cass was a pale - skinned , older man who sported short gray hair . Within the Imperial military , he was considered a model adjutant . However , despite his reputation for being self - possessed and discreet , Cass still was wary of Tarkin ' s wrath , and he disliked being the one bearing bad news to the Moff . Behind the scenes . Siward Cass made his first appearance in the 1977 , in which he was portrayed by English actor Patrick Jordan . Albeit unnamed in the movie itself , he was referred to as " Cass " in its . Although Cass was sometimes identified as a general by fan - created sources , he was initially only referred to in canon as " Imperial Officer Cass " or " Officer Cass , " and his exact rank long remained unknown . Unlike most characters whose names are known in the script , Officer Cass did not have an entry in the StarWars . com official Databank . In 2013 , Cass was eventually given the first name " Siward " and the rank of " Chief " in both the " Death Star Owner ' s Technical Manual " and the article " The Death Star Coup " , written by Jason Fry for the Special Edition 2014 of the " Star Wars Insider " magazine . According to Chris Trevas , one of the co - authors of the " Technical Manual " , Cass was given that rank because his insignia plaque was the same one as Moradmin Bast ' s , who was first identified as " Chief Bast " in the " Star Wars " Customizable Card Game Premiere Limited expansion set . Fry chose the character ' s first name as a nod to play " " , which featured the character of , general of the English forces . The 2008 novel " Death Star " featured an unidentified colonel serving as Tarkin ' s aide , although it is not clear whether he was intended to be Cass or not .