Constantine Doukas

Who was Constantine Doukas?

Constantine Doukas or Ducas, was Byzantine co-emperor from c. 1074 to 1078 and from 1081 to 1087. He was the son of Emperor Michael VII Doukas and his Georgian wife Maria of Alania.

Constantine was porphyrogennētos, i.e., born in the purple, and was associated on the throne by his father soon after his birth. He was quickly involved in imperial diplomacy, as the infant was betrothed to Olympias of Apulia, renamed Helena, the daughter of the Norman leader Robert Guiscard and Sikelgaita. After his father was forced to abdicated in 1078, Constantine's mother Maria married the new Emperor Nikephoros III Botaneiates, but failed in convincing him to recognize the imperial status and succession rights of her son. Constantine's demotion also involved the breaking off of the engagement to the daughter of Robert Guiscard, who used this as pretext to commence military action against the Byzantine Empire.

After the fall of Botaneiates in 1081, Maria's intimacy with his successor Alexios I Komnenos and the latter's policy of alliance with the Doukas family brought about Constantine's restoration as co-emperor.