The son, however, did not forget his mother, and when Constantine became emperor in 306 c.e., he had her raised to a place of honor, which culminated in the title of Augusta (emperor’s mother). Constantine also renamed the place of her birth Helenopolis in her honor.
According to the early church historian Eusebius, Helena’s conversion to Christianity was due to the influence of her son; but Theodoret’s more credible account is that the mother nurtured in her son openness to the faith.
Nonetheless, she bore religious stature and sanctity in her own right and had remarkable influence on her son. Constantine had his second wife, Fausta, and their son Crispus executed. His mother had acted not in support of her daughter-in-law but rather had been involved in bringing about her downfall.
Helena took to the Christian faith with zeal, as is testified by her piety, her generosity to the poor, and her devotion to the sacred places of pilgrimage in Palestine, revered by early Christians as the Holy Land.
In 326, Helena, well into her 70s, went on pilgrimage there. She stayed in Palestine for some time, exercising her right to the imperial treasury by having two major basilicas built in great splendor, one in Bethlehem (Church of the Nativity) and one on the Mount of Olives (Church of the Ascension).
At the same time, her son was having the Church of the Holy Sepulcher built over the sites of Jesus (Christ) of Nazareth’s death and resurrection. Her collaboration with her son caused church architecture to create a Christian landscape throughout the empire, in the Holy Land, Rome, and Constantinople.
The discovery of the "True Cross" (thought to be that upon which Jesus died) is attested to by Cyril of Alexandria and Egeria, but the tradition that sprang up at the end of the fourth century c.e. (mentioned by Ambrose, Sulpicius Severus, and Ruﬁ nus) that Helena had discovered the True Cross and that it was identified by a miracle seems likely to be an embellishment, given Eusebius and Cyril’s silence on this point.
She supposedly had this precious relic deposited in Rome at the Church of Santa Croce, which she built especially for this purpose. Her renown, however, rests firmly on the facts that she was a woman of immense power and wealth who spent the latter part of her life in acts of Christian charity.
Her close identification with her son, Constantine, set the model for the role of the Christian Augusta for subsequent centuries. Her feast is celebrated on August 18 in the Latin Church calendar and on May 21 (along with her son) in the Greek Church calendar.