This is the extended edition including an extensive primer on the author's life and works, as well as a detailed essay about the history of the Longfellow translation. The "Divina Commedia" is an allegory of human life, in the form of a vision of the world beyond the grave, written avowedly with the object of converting a corrupt society to righteousness: "to remove those living in this life from the state of misery, and lead them to the state of felicity". It is composed of a hundred cantos, written in the measure known as terza rima, with its normally hendecasyllabic lines and closely linked rhymes, which Dante so modified from the popular poetry of his day that it may be regarded as his own invention. He is relating, nearly twenty years after the event, a vision which was granted to him (for his own salvation when leading a sinful life) during the year of jubilee, 1300, in which for seven days (beginning on the morning of Good Friday) he passed through hell, purgatory, and paradise, spoke with the souls in each realm, and heard what the Providence of God had in store for himself and to world.