Later medieval Irish literature, written centuries after Primitive Irish had already evolved into Old Irish, credits the invention of Ogham to Ogma, a god associated with eloquence and physical strength in the mythological Tuatha De Danann, and the eleventh or twelfth century tract known as the Auraicept na nEces builds an elaborate legendary history around the script's origin that has no independent confirmation from the inscriptions themselves.
Whatever the truth of that attribution, which most scholars read as retrospective myth-making rather than a real record of the script's invention, Ogham's actual function in the surviving corpus is resolutely practical: marking graves, recording ownership, and asserting a lineage claim on land or monument through the formula naming a man as his father's son. This gap between Ogham's modest, formulaic archaeological reality and its much grander later legendary reputation, as a sacred or druidic secret alphabet, mirrors a pattern common to many ancient scripts reinterpreted by later esoteric traditions, and modern occultism has in turn built an entire divinatory system, the Ogham staves, onto the alphabet's twenty characters, treating each as a tree and a symbolic meaning largely disconnected from anything the fourth to sixth century inscriptions themselves demonstrate. Primitive Irish, the language the stones actually preserve, remains the more modest and better attested of the two stories.