" Gryffindor house is home to Nearly Headless Nick, who in life was Sir Nicholas de Mimsy-Porpington. Something of a snob, and a less accomplished wizard than he believed, Sir Nicholas lounged around the court of Henry VII in life, until his foolish attempt to beautify a lady-in-waiting by magic caused the unfortunate woman to sprout tusks. Sir Nicholas was stripped of his wand and inexpertly executed, leaving his head hanging off by a single flap of skin and sinew. He retains a feeling of inadequacy with regard to truly headless ghosts. Another "

― J.K. Rowling , Hogwarts: An Incomplete and Unreliable Guide (Pottermore Presents, #3)