Bardas Bardas ( ; died 21 April 866 ) was a Byzantine noble and high - ranking minister . As the brother of Empress Theodora , he rose to high office under Theophilos ( r . 829 – 842 ) . Although sidelined after Theophilos ' s death by Theodora and Theoktistos , in 855 he engineered Theoktistos ' s murder and became the " de facto " regent for his nephew , Michael III ( r . 842 – 867 ) . Rising to the rank of " Caesar " , he was the effective ruler of the Byzantine Empire for ten years , a period which saw military success , renewed diplomatic and missionary activity , and an intellectual revival that heralded the Macedonian Renaissance . He was assassinated in 866 at the instigation of Michael III ' s new favourite , Basil the Macedonian , who a year later would usurp the throne for himself and install his own dynasty on the Byzantine throne . Biography . Early life . Bardas was born to the " droungarios " Marinos and Theoktiste , and was the elder brother of Empress Theodora , the wife of Emperor Theophilos , and of Petronas . Three other sisters , Maria , Sophia , and Irene , are recorded by Theophanes Continuatus . The family was of Armenian origin and had settled in Paphlagonia . Some modern genealogists , including Cyril Toumanoff and Nicholas Adontz , have suggested a link of Bardas ' family with the Armenian noble clan of the Mamikonian . According to Nina Garsoïan in the " Oxford Dictionary of Byzantium " , however , " [ a ] ttractive though it is , this thesis cannot be proven for want of sources . " In 837 , Theophilos raised him to the rank of " patrikios " and sent him together with the general Theophobos in a campaign against the Abasgians , but the Byzantines were defeated . With the death of Theophilos , the young Michael III ( r . 842 – 867 ) ascended the throne . As he was only two years old , a regency council was set up headed by Theodora . Bardas and his brother Petronas , as well as their relative Sergios Niketiates , were also members , but it was the logothete Theoktistos who quickly established himself as Theodora ' s chief advisor . Bardas still played an active role in the early days of the regency , encouraging Theodora to abandon Iconoclasm for good and taking part in the investigations that led to the deposition of the pro - iconoclast patriarch John the Grammarian and the restoration of the veneration of icons in 843 . In 844 , however , Theoktistos blamed Bardas for the desertions that led to the Byzantine defeat in the Battle of Mauropotamos against the Abbasids , even though the logothete himself led the Byzantine army , and had him exiled from Constantinople . Following Bardas ' s exile and the death of Sergios , Theoktistos ruled supreme alongside Theodora for a decade . In 855 , Michael III turned fifteen and thus came nominally of age . His mother and Theoktistos arranged a bride show and selected Eudokia Dekapolitissa as his bride , disregarding Michael ' s attachment to his mistress , Eudokia Ingerina . Bardas used Michael ' s resentment for the high - handed manner in which he was treated and began to turn him against the regency . With Michael ' s backing , Bardas was allowed to return to the capital , and on 20 November 855 , Theoktistos was murdered . This was possibly done at the emperor ' s behest , for Bardas is said to have favoured a more " elegant " removal of his rival . Ascendancy and fall . With the death of Theoktistos , the regency was at an end ; in early 856 , Michael proclaimed his assumption of full imperial power , and in 857 Theodora was forced to retire to the Gastria Monastery . Nevertheless , as Michael was more interested in his pleasures and his continuing affair with Eudokia Ingerina , Bardas now became the " de facto " regent of the Empire . By ca . 858 he was promoted to the highest state offices ( " magistros " and " chartoularios tou kanikleiou " ) , followed by his promotion to " kouropalates " — according to Symeon Logothetes , this happened after a failed assassination attempt masterminded by Theodora — and finally , on 22 ( or 26 ) April 862 , to " Caesar " . Petronas also emerged from obscurity at the same time , becoming " strategos " of the Thracesian Theme and leading a series of successful raids against the Arabs . Although later sources are critical of his character , describing him as vain , avaricious and power - hungry , his capabilities as an administrator are widely acknowledged . Thus Bardas founded the Magnaura School with seats for philosophy , grammar , astronomy and mathematics , supported scholars like Leo the Mathematician and promoted the missionary activities of Cyril and Methodius to Greater Moravia . He also scored a number of successes against the Arabs in the East , culminating in the decisive Battle of Lalakaon in 863 , and enforced the Christianization of Bulgaria by Byzantine missionaries . The " Patria of Constantinople " praise him also for his building activity , but aside from a church dedicated to Saint Demetrius outside the city itself , most of the buildings attributed to him were probably the work of Basil I the Macedonian ( r . 867 – 886 ) . In 858 , Bardas deposed patriarch Ignatios and appointed Photios , well - educated but a layman , in his stead . Later chronicles report that Ignatios had excluded Bardas from communion because he maintained an incestuous relationship with one of his daughters - in - law , but the real reason for Ignatios ' s deposition was probably the patriarch ' s staunch refusal to tonsure Empress Theodora against her will , as demanded by Bardas . The irregular elevation of Photios , however , riled with Pope Nicholas I , who refused to recognize it . Coupled with competition between Rome and Constantinople over their missionary activities in and jurisdiction over Moravia and Bulgaria , relations with the papacy remained tense . Despite his great authority , Bardas ' s control over his nephew was not absolute : after he managed to persuade him to dismiss his old chamberlain ( " parakoimomenos " ) , Michael appointed to the post not one of Bardas ' s own protégés , but his favourite companion , the ruthlessly ambitious Basil the Macedonian . Bardas ' s own position was further weakened in 866 , when Michael learned that Eudokia Ingerina was pregnant to the future Leo VI , as hitherto his uncle stood to succeed him if anything should happen to the emperor . Instead of divorcing his wife and marrying his long - time mistress , however , Michael married off Ingerina to Basil instead , who divorced his own wife first . Finally , in spring 866 Bardas began assembling a large - scale expedition against the Saracen stronghold of Crete . Accompanied by Michael , Basil and the court , Bardas made for Miletus , where the army was assembling . There , on 21 April 866 , he was murdered by Basil , ostensibly for plotting against the emperor . The campaign was abandoned while Michael and Basil returned to Constantinople , where Michael adopted his friend and made him co - emperor . In September 867 , Basil had Michael III assassinated as well , ending the Amorian Dynasty and inaugurating the Macedonian period of Byzantine history . Family . Bardas was married twice . From his unknown first wife , who must have died before 855 , he had a son named Antigonos , a daughter named Irene , an unnamed son and another daughter who married the logothete Symbatios ( although she may be identical with Irene ) .