It was the story of Constantine and Helena that started the sublimation of the cross into Christianitys main symbol. The Byzantine Empire minted coins showing Constantine raising a cross like a banner; Christians started using the cross as pectorals, grave markers and objects of veneration in their homes; churches began displaying them on spires; some were even constructed with cruciform ground plans; by the 13th century, the cross was endemic throughout Christendom.
English literature may be said to have begun with Helena and the cross.
Two of the oldest English poems (8th century or earlier) are Cynewulfs Elene and the anonymous Dream of the Rood; the former was an English variant of Helenas finding of the true cross; the latter anthromoporphized the cross by making it express, first, its humiliation at the hands of those who transformed it from a tree to an instrument of execution; second, its humility upon seeing who its occupant would be; third, its glory when it becomes the restored tree of salvation. More than a millenium later, St. Teresa of Avila would echo the same sentiments:
Oh, Cruz, madero precioso,
Lleno de gran majestad,
Pues siendo de despreciar
Tomaste a Dios por esposo!
On July 26, 1960, Pope John XXIII decreed the abolition of the Invention of the Cross.