Theodora Porphyrogenita (; 31 August 1056) was Byzantine Empress from 21 April 1042 to her death on 31 August 1056, and sole ruler from 11 January 1055. She was the last sovereign of the Macedonian dynasty that ruled the Byzantine Empire for almost 200 years.
Theodora was the youngest daughter of Emperor Constantine VIII. After Theodora's father died in 1028, her older sister Zoë co-ruled with her husbands Romanos III and Michael IV, kept Theodora closely watched. After two foiled plots, Theodora was exiled to an island monastery in the Sea of Marmara in 1031. A decade later, the people of Constantinople rose against Michael IV's nephew and successor, Michael V, and insisted that Theodora return to rule alongside Zoë.
After 65 days Zoë married again, to Constantine IX, who assumed the imperial responsibilities. Theodora seemingly retired to a convent after Zoë's death in 1050. When Constantine died, the 74-year-old Theodora returned to the throne despite fierce opposition from court officials and military claimants. For 16 months she ruled as empress in her own right before succumbing to a sudden illness and dying at 76. She was the last ruler of the Macedonian line.
Early life
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Theodora was the third and youngest daughter of Byzantine Emperor Constantine VIII and Helena, daughter of Alypius. She was a Porphyrogenita, "born into the purple"; the appellation for a child born in the capital to a reigning emperor. Her father became co-emperor in 962 and sole emperor upon the death of his brother Basil II in 1025. His reign as sole emperor lasted less than three years, from 15 December 1025 to 12 November 1028. Consequently, Theodora lived a life of virtual obscurity in the imperial gynaeceum (women's quarters). Theodora further claimed that since Romanos and she were third cousins, it was too close a blood relationship for marriage to occur.
A purge of senior officials and the leadership of the European military units followed. Nikephoros Proteuon was arrested at Thessalonica and forcibly tonsured. Nikephoros Bryennios, whom the western tagmata apparently wanted to proclaim emperor instead, was dismissed and exiled on Theodora's orders,
When Theodora was seventy-six, the patriarch Michael Keroularios advocated that Theodora advance a subject to the throne through marriage to her, in order to assure a succession. She refused to consider marriage, no matter how token. She also refused to name an heir to the throne. Theodora became gravely ill with an intestinal disorder in late August 1056. On 31 August her advisors, chaired by Leo Paraspondylos, met to decide whom to recommend to her as a successor. According to Psellus, they selected Michael Bringas, an aged civil servant and former military finance minister whose main attraction was that "he was less qualified to rule than he was to be ruled and directed by others". Theodora was unable to speak, but Paraspondylos decided that she had nodded at an appropriate moment. Hearing of this the Patriarch refused to believe it. Eventually he was persuaded and Bringas was crowned as Michael VI. Theodora died a few hours later and with her death, the Macedonian dynasty's 189-year rule ended.