Athelstan, who was the eldest son of King Edward the Elder and Ecgwynn was born in 895 during the latter years of the reign of his grandfather, King Alfred the Great. Very little is known about Athelstan's mother. Some sources describe her as a "common law wife". There are reasons to suspect that she was of low social status for a prince's wife. The marriage or relationship of Edward and Ecgwynn appears to have come to end before Edward became king.
Athelstan is recorded as being a tall and handsome youth with light flaxen hair. As a youth, he had been ennobled by his grandfather, of whom he was said to be a great favourite. To mark the occasion King Alfred endowed his grandson with a mantle of royal purple, a girdle set with precious stones and a Saxon seax (sword) in a golden scabbard. Described in the Gesta Regum Anglorum of William of Malmesbury (c.1080-1143) as 'of handsome appearance and graceful manners... [N]ot beyond what is pleasing in stature and slender in body; his hair, as we ourselves have seen from his relics, flaxen, with gold threads.'