Grendreef was an admiral in the naval branch of the Galactic Empire's Imperial Military. Alliance to Restore the Republic intelligence officer Cassian Andor served undercover for a time using the operational alias "Joreth Sward" as Grendreef's assistant at some point prior to Andor's death in the year 0 BBY.
Behind the scenes
Grendreef was first mentioned in the reference book Star Wars: Rogue One: The Ultimate Visual Guide, which was written by Pablo Hidalgo and released on December 16, 2016. Grendreef first appeared in the Star Wars Legends continuity as one of the villains in The Isis Coordinates, an adventure written by Christopher Kubasik and released in June, 1990 for West End Games' Star Wars: The Roleplaying Game.
- Star Wars: Rogue One: The Ultimate Visual Guide (First mentioned)
- Star Wars: Absolutely Everything You Need to Know, Updated and Expanded
- "The Heroes of Rogue One" – Star Wars Encyclopedia