Cylaces or Glak (Old Armenian: Գղակ, romanized: Głak, misspelled Դղակ, Dłak in the manuscripts of Faustus of Byzantium's history) was a 4th-century Armenianeunuch who occupied the office of hayr-mardpet (grand chamberlain). He initially defected to the Sasanian side during Shapur II's invasion of Armenia, but later rejoined the Armenians in 368 and fought Shapur II's forces.[1] In 370, he sent messengers to Shapur II, promising him to betray the Armenian king Pap (r. 370–374). However, this ploy was discovered by Pap, who had Cylaces assassinated.[2][3]
In Faustus of Byzantium'sHistory of Armenia, Cylaces is split into two characters, both of whom are executed on Pap's orders: an unnamed hayr-mardpet who is executed for insulting Pap's mother Parandzem, and another one named Glak who is executed for conspiring with the Persians.
Lenski, Noel Emmanuel (2002). Failure of Empire: Valens and the Roman state in the fourth century A.D. University of California Press. ISBN978-0-520-23332-4.
Syvanne, Ilkka (2015). Military History of Late Rome 284–361. Pen & Sword.
