Constantine Doukas (co-emperor) in the context of "John Doukas (Caesar)"

The Byzantine Empire was ruled by emperors of the Doukas dynasty between 1059 and 1081. There are six emperors and co-emperors of this period: the dynasty's founder, Emperor Constantine X Doukas (r. 1059–1067), his brother John Doukas, katepano and later Caesar, Romanos IV Diogenes (r. 1068–1071), Constantine's son Michael VII Doukas (r. 1071–1078), Michael's son and co-emperor Constantine Doukas, and finally Nikephoros III Botaneiates (r. 7 January 1078 – 1 April 1081), who claimed descent from the Phokas family.

Under the rule of the Doukids, Byzantium was fighting a losing battle against the Seljuk Turks, losing most of its remaining possessions in Asia Minor following the catastrophic defeat at the Battle of Manzikert in 1071 and the following civil war after the death of Romanos IV Diogenes.Byzantium also incurred substantial loss of territory in the Balkans, to the Serbs, as well as losing its final foothold in Italy, to the Normans.

Anna Komnene (Greek: Ἄννα Κομνηνή, romanized: Ánna Komnēnḗ; 1 December 1083 – 1153), commonly Latinized as Anna Comnena, was a Byzantine Greek historian. She is the author of the Alexiad, an account of the reign of her father, Byzantine emperor Alexios I Komnenos. Her work constitutes the most important primary source of Byzantine history of the late 11th and early 12th centuries, as well as of the early Crusades. Although she is best known as the author of the Alexiad, Anna played an important part in the politics of the time and attempted to depose her brother John II Komnenos as emperor in favour of her husband, Nikephoros Bryennios the Younger.

At birth, Anna was betrothed to Constantine Doukas, and she grew up in his mother's household. She was well-educated in "Greek literature and history, philosophy, theology, mathematics, and medicine." Anna and Constantine were next in the line to throne until Anna's younger brother, John II Komnenos, became the heir in 1092. Constantine died around 1094, and Anna married Nikephoros Bryennios in 1097. The two had several children before Nikephoros' death around 1136.