What were Pre-Raphaelite paintings often based on?

Pre-Raphaelite paintings were often based on literature, mythology, and historical themes, drawing inspiration from works by authors like Dante, Shakespeare, and Keats. The movement sought to capture intense emotion and vivid detail, often incorporating symbolic elements to convey deeper meanings. Additionally, they emphasized a return to nature and medieval aesthetics, reflecting a reaction against the industrialization and academic conventions of their time.