Can do no better than to quote the great Robert Rosenblum:

"One of the pioneers in this exploration of the irrational [in the Romantic movement] is the Swiss-born but thoroughly cosmopolitan HENRY FUSELI (1741-1825) who thrilled audiences with his prolific displays of the stuff that dreams are made of. (Shakespeare) provided him as well as contemporaries with an especially wide spectrum of imaginative possibilities. (Entrepreneur John Boydell) commissioned a group of British artists to paint illustrations for his new "Shakespeare Gallery" which opened in 1789. (Here in his illustration from A Midsummer Night's Dream, 1790, Tate Gallery)) we are levitated to a gravity-defiant world presided over by Titania queen of the fairies who has just conjured up an ectoplasmic whirlwind of her elves, sprites and gnomes to attend to Bottom . . . This murky fluid world seems charged with a curious erotic fantasy in which voluptuously attenuated women, like the one on the right who leads the tiny old dwarf on a string, dominate the scene like giddy but imperious courtesans. An almost exact contemporary of the Marquis de Sade, Fuseli seems also to be investigating the more extravagant regions of the sexual imagination, though here given more public propriety thru the Shakespearean source. . . the bizarre and morbid character of his art has an intensely personal ring . . ."