Royen was a moff within the Galactic Empire throughout the duration of the Galactic Civil War. Following the Battle of Endor in 4 ABY, which resulted in the death of Emperor Palpatine, Royen's fleet found itself isolated from Imperial reinforcements in the vicinity of the Red Hand Cluster, thereby effectively transforming it into an independent Imperial breakaway group. The isolation of Royen's fleet was referenced by Caern Adan, a New Republic agent working for their Intelligence branch, during a discussion with General Hera Syndulla and the New Republic's Alphabet Squadron.
The character Royen was first brought up in Alphabet Squadron, a 2019 novel and the initial book in the Star Wars: Alphabet Squadron series authored by Alexander Freed.