"they should have put the brand of a hot iron on Hester Prynne’s forehead"
Burning letter A
Creative Commons AttributionBurning letter A - Credit: Paulg7
Branding iron
Creative Commons AttributionBranding iron - Credit: SearchNetMedia

Hawthorne is not embellishing the past here: such cruel punishments were indeed meted out to adulterers. He may be thinking particularly of Mary Batchellor, the wife of an octogenarian minister from whom she had separated. When Mary became pregnant with the child of one George Rogers in 1650, both parties were sentenced to 39 lashes of the whip (the maximum number, since 40 were deemed to be fatal) and Mary was branded with the letter A. The scant details of the case are recorded here.