Bede (Bædæ - as written on his tomb stone) wrote about the poet and his work in his Historia ecclesiastica gentis Anglorum, book 4, chapter 24. According to Bede, Cædmon was an illiterate cow-herder "who was actually employed by the monastery of Whitby" and who miraculously was able to recite a Christian song of creation in Old English verse. This miracle happened after Cædmon left a feast when they were passing a harp around for all to sing a song. He left the hall after feeling ashamed that he could not contribute a song. Later in a dream he said a man appeared to him and asked him to sing a song. Cædmon responded that he could not sing, yet the man told him that he could and asked him to "Sing to me the beginning of all things." Cædmon was then able to sing verses and words that he had not heard of before. Cædmon then reported his experience first to a steward then to Hild, the abbess of Whitby. She invited scholars to evaluate Cædmon’s gift, and he was sent home to turn more divine doctrine into song. The abbess was so impressed with the success of his gift that she encouraged him to become a monk. He learned the history of the Christian church and created more music like the story of Genesis and many biblical stories which impressed his teachers. Bede says that Cædmon in his creation of his songs wanted to turn man from love of sin to a love of good deeds. Cædmon is said to have died peacefully in his sleep after asking for the Eucharist and making sure he was at peace with his fellow men.
Like many Old English and Anglo-Latin pieces, it was designed to be sung aloud and was never physically recorded by Cædmon himself, but was written and preserved by other literate individuals. The Hymn itself was composed between 658 and 680, recorded in the earlier part of the 8th century, and survives today in at least 19 verified manuscript copies. The Hymn is Cædmon's sole surviving composition.
The poem forms a prominent landmark and reference point for the study of Old English prosody, for the early influence which Christianity had on the poems and songs of the Anglo-Saxon people after their conversion.
Cædmon's Hymn is the oldest recorded Old English poem, and also one of the oldest surviving samples of Germanic alliterative verse. Within Old English, only the inscriptions upon the Ruthwell Cross (doubtful) or Franks Casket (early 8th century) may be of comparable age. Outside of Old English, there are a few alliterative lines preserved in epigraphy (Horns of Gallehus, Pforzen buckle) which have a claim to greater age.