Historians examining the textual history of the True Cross discovery narrative note a significant gap between the traditional 320s date of Helena's visit to Jerusalem and the earliest surviving detailed accounts of the discovery itself, which appear only in writers active several decades later, in the closing years of the fourth century, a gap that has led most historians to treat the specific finding narrative, as opposed to Helena's broader documented activity in Jerusalem, as a later pious tradition that developed and elaborated over time rather than as an event recorded by contemporaries.
Eusebius of Caesarea, writing a detailed account of Constantine's building activity in Jerusalem closer to the actual events, describes the uncovering of the tomb associated with Jesus's burial in some detail but does not mention the discovery of the cross itself, a silence scholars generally regard as significant evidence that the specific cross narrative developed after, rather than alongside, the earlier and better attested account of the tomb's discovery.
Whatever the precise historical mechanics of its origin, the True Cross tradition became enormously influential in subsequent Christian devotional life, generating a vast later literature and an extensive practice of relic veneration that shaped medieval Christian piety, pilgrimage and church architecture for many centuries following the events the original narrative describes.