Paradise Lost is frequently interpreted as a political allegory: though it clearly presents the story of mankind's and Satan's fall from grace, Milton's known allegiance to Oliver Cromwell (the statesman who overthrew King Charles I during the English Civil War) suggests that he may have intended the epic poem to be a commentary on the events of the Civil War, with Cromwell standing in for Satan, and God for King Charles I.
This interpretation could help to explain why Satan is portrayed with both good and bad character traits—regret, sorrow, and shame in addition to malice and deception. Milton's views of Cromwell were not exactly straightforward: he considered himself a Republican, while many viewed Cromwell's Protectorate (the new form of government he created) as a pale imitation of Republicanism (Milton himself was ambivalent, but also engaged in sharp critiques of Cromwell). So, in other words, in Milton's portrayal of the interactions between God and Satan throughout the poem, readers should look for hints that Milton didn't think entirely kindly of King Charles's reign (as allegorically portrayed by God in Heaven), yet also found sufficient fault with Cromwell (Satan) that he didn't hold back from criticizing the latter's motives and actions quite trenchantly.
