Leo I the Thracian
Constantine Opos first appears in the "Alexiad" in 1081, during Alexios's campaign against the Normans of Robert Guiscard, leading the "tagma" of the "Exkoubitoi". The campaign ended in the Byzantine defeat at the Battle of Dyrrhachium on 18 October 1081, which effectively shattered the last remains of the old-established regiments of the middle Byzantine army. The "Exkoubitoi" are never heard from again; their remnants were probably disbanded, marking the end of this historic unit, which had been founded as an elite imperial bodyguard by Emperor Leo I the Thracian (r. 457–474).