Dante's History
The poem is allegorical, with multiple meanings. Each episode will cover a canto at a time, summarizing and interpreting the poem based on dozens of commentaries. Check the website for further reading.
Dante and Virgil are in the 8th bolgia where they meet a former warlord turned friar who broke his vows to help a contested pope defeat his enemies. Though he was promised absolution, he would be the cause of his own damnation.