The Romantic movement rebelled against the strictures of the Enlightenment.
If the ultimate value for the Enlightenment had been reason, now
it was passion. Passion (or will) + power = creativity.
The Romantics found creativity to be God's greatest attribute, and therefore
they also sought to create.
According to traditional, reason should govern passion. Romanticism
reversed the hierarchy--passion now ruled reason. Where ambition
and rebellion had been traditional vices, now they were virtues.
Thus in this period Milton's Satan could change from villain to hero.