John Doukas (megas doux)

John Doukas
Born	ca. 1064
Died	before 1136
Allegiance	Byzantine Empire
Rank	megas doux
Battles/wars	Byzantine–Seljuk Wars
Relations	Michael Doukas (brother)

John Doukas (Greek: Ἰωάννης Δούκας, ca. 1064 – before 1137) was a member of the Doukas family, a relative of Byzantine emperor Alexios I Komnenos (r. 1081–1118) and a senior military figure of his reign. As governor of Dyrrhachium, he secured the imperial possessions in the western Balkans against the Serbs. Appointed megas doux, he scoured the Aegean of the fleets of the Turkish emir Tzachas, suppressed rebellions in Crete and Cyprus, and then recovered much of the western coast of Anatolia for Byzantium.

John Doukas was born circa 1064, the second son of the domestikos ton scholon Andronikos Doukas, son of the Caesar John Doukas, and his wife, Maria of Bulgaria, the granddaughter of Tsar Ivan Vladislav of Bulgaria (r. 1015–1018). John was thus the brother-in-law of Alexios I Komnenos, who had married his sister Irene Doukaina. In 1074, during the rebellion of the Norman mercenary Roussel de Bailleul, John, along with his elder brother Michael, was at his grandfather the Caesar's estates in Bithynia. Roussel demanded that the Caesar give up the two as hostages in return for releasing their wounded father, whom he held captive. The elder John Doukas agreed, and the two were imprisoned by Roussel; Michael managed to escape, but the younger John remained with Roussel until the latter's defeat and capture by the Turks of Artuk later in the year.

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