Justin I
Sittas's origin is obscure. Byzantinists have suggested his name was Gothic or Thracian, but his theoretical descent from either the Goths or the Thracians is not mentioned in primary sources. He enters history in the reign of Emperor Justin I (r. 518–527) as a "doryphoros" ("bodyguard") in the guard of Justinian, then "magister militum per Orientem".