The Conflict between Church and StateThe ongoing struggle between papal authority and imperial power, as critiqued throughout the Comedy.1The Donation of ConstantineIn the Inferno, Canto XIX, and Paradiso, Canto XX2The Two SunsIn Purgatory, Canto XVI, Marco Lombardo's discourse3The Corruption of the PapacyThroughout the Comedy, especially in Inferno and Paradiso4The Ideal EmperorIn Paradiso, Canto VI and XXX5The Ghibelline and Guelph ConflictThroughout the Comedy, especially in Inferno and Purgatorio