Sittas Sittas ( ; died 538 ) was a Byzantine military commander during the reign of Emperor Justinian I ( r . 527 – 565 ) . During the Iberian War against the Sassanid Empire , Sittas was given command of forces in Armenia , similar to the status of Belisarius in Mesopotamia . He won a victory over the Sassanids at Satala . Biography . Sittas was the husband of Comito , the elder sister of the Empress Theodora , and possible father of the later empress Sophia . 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 " . In 527 , Sittas and Belisarius were given command of an invasion of Persarmenia . They were successful in looting the area and capturing a significant number of Armenian prisoners . They attempted to invade the rest of the Marzpanate of Armenia later in the year but were defeated by Aratius and Narses . The latter should not be confused with Narses , another Byzantine general under Emperor Justinian . In 528 , Sittas was appointed in the new office of " magister militum per Armeniam " . According to both Malalas and Theophanes the Confessor , Sittas recruited his " scriniarii " ( administrative officials ) among the local Armenian populace , as he considered them more familiar with the territory . Procopius records Sittas ' s victory over the Tzanni , a tribe of the Caucasus , which led occasional raids in neighbouring areas . Sittas successfully converted them from Paganism to Christianity and recruited the former brigands to the Byzantine army . In 530 , Sittas also received the office of " magister militum praesentalis " ( " Master of soldiers in the Presence [ of the Emperor ] " ) . That same year , Sittas and Dorotheus defended Theodosiopolis against an invading force from the Sassanid Empire , part of the ongoing Iberian War between Emperor Justinian and the Persian shah , Kavadh I ( r . 488 – 531 ) . Procopius notes that the Roman forces managed to pillage the enemy camp . Sittas also defended Satala against the invasion force by attacking the larger army at its rear and forcing them to retreat ( Battle of Satala ) . The invasion was called off and the Sassanids retreated back to Persia following the two defeats . Following the defeat of Belisarius in the Battle of Callinicum ( 19 April 531 ) , Sittas replaced him in the leadership of the Persian campaign . Kavadh , however , died within the year , and his son and successor Khosrau I ( r . 531 – 579 AD ) was interested in stabilizing his internal position for the time being and started negotiations for a peace . The " Eternal Peace " agreement ( which eventually lasted ten years ) was signed on September 532 on the terms of all Byzantine land lost under Emperor Justinian ' s rule to be returned , and the Byzantines to pay heavy tribute in exchange for peace . The country of Iberia remained under Sassanid control . Sittas received the honorific title of patrician in 535 . The same year , Sittas is credited with a victory against the Bulgars in Moesia , by the Iatrus ( Yantra ) . He was named an honorary consul in 536 . In 538 / 539 , Sittas was sent back to Armenia to face a revolt in protest against heavy taxation . Failing to negotiate peace , Sittas started active fighting . In the Battle of Oenochalcon , the nature of the terrain forced both armies to fight in scattered groups rather than in unified forces . Procopius records that Sittas was killed by either Artabanes , a leader of the revolt , or Solomon , an otherwise obscure rebel .