E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
A sensation in sleep as if something heavy were sitting on our breast. (Anglo-Saxon, mara, an incubus.) This sensation is called in French cauchemar. Anciently it was not unfrequently called the night-hag, or the riding of the witch. Fuseli used to eat raw beef and pork chops for supper to produce nightmare, that he might draw his horrible creations. (See MARES NEST.)
I do believe that the witch we call Mara has been dealing with you.Sir Walter Scott: The Betrothed, chap. xv.
Nightmare of Europe. Napoleon Bonaparte (1769, 18041814, 1821).