Helena, daughter of Alypius was a Byzantine Empress consort as the wife of Byzantine Emperor Constantine VIII.
Very little is known about her, as she is only briefly mentioned in the Chronographia of Michael Psellos, followed in the works of John Skylitzes and the Zonaras. Psellos writes of her only that:
"Constantine while still a young man, had married a lady called Helena. She was a daughter of the renowned Alypius, then the leading man in the city and member of a noble family held in high repute. This lady, who was not only beautiful but also virtuous, bore him three daughters before she died."
Apart from this reference in Psellos, her father Alypius is otherwise unknown. The marriage probably took place ca. 976, and Helena died at some unknown point, apparently long before her husband became sole emperor in 1025. The historian Gunther G. Wolf theorized that she died ca. 989, possibly during the birth of her third daughter.
Their three daughters were:
At the time of their marriage Constantine VIII was the co-ruler of his older brother Basil II. Basil reigned as senior Byzantine Emperor from 976 to 1025 but never married, which would make Helena the only Augusta during his reign.
Ronald Wells, a modern genealogist, has suggested that Eudokia did not remain a nun for life. He has theorised an identification of Eudokia with the otherwise unnamed wife of Andronikos Doukas, a Paphlagonian nobleman who may have served as governor of the theme of Moesia. This theory would make Helena a maternal grandmother of Constantine X and John Doukas.
Wells has further suggested two daughters of the above proposed union. The first suggested daughter is Maria, the wife of Ivan Vladislav. Christian Settipani has however posited a more robustly argued descent of Maria from Tsar Boris II of Bulgaria. The second daughter is "Sophia", an alleged wife of Manuel Erotikos Komnenos. Manuel was the father of Isaac I Komnenos and John Komnenos, the latter being the father of Alexios I Komnenos.