Dante's Inferno, how does this relate to medieval times?

Especially after examining canto IV and XXXIV (which describe the first and last circles of hell) how do the specific descriptions and insights from these two passages reflect aspects of this medieval vision of the universe? This is in consideration of such issues like the rationale for an individuals placement in and within hell (including the concept of symbolic retribution) Christian theology in gemeral, and the medieval notion of the physical structure of the universe.