The Hogwarts ghosts represented the four houses of Gryffindor, Slytherin, Ravenclaw and Hufflepuff in their own unique ways. Here's our guide to those who haunted Hogwarts.
A fifteenth-century nobleman who went to Hogwarts. His real name was Sir Nicholas de Mimsy-Porpington.
Nick, a wizard at the royal court of Henry VII, fell in love with Lady Grieve. After trying to magically fix her crooked teeth, the spell backfired, Lady Grieve grew tusks, and Nick was sentenced to death for his actions.
Nick wrote a ballad about his own demise, entitled The Ballad of Nearly Headless Nick.
The morose daughter of the Ravenclaw house founder, Rowena Ravenclaw. Her real name was Helena.
In a horrible way, frankly. After stealing her mother's diadem and running away, Rowena Ravenclaw sent The Baron to retrieve her. Alas, it didn't go so well. The Baron, mad with jealousy at Helena's freedom, ended up stabbing her when she refused to return with him. Helena's ghost had a 'single dark wound' upon her chest as a result.
The 'forest in Albania' where Helena would go into hiding was also frequented by Lord Voldemort. Eventually, the enchanted diadem would become one of Voldemort's Horcruxes, after he discovered its hiding place in a hollowed tree.
A jolly fellow who resembled a monk, who was sorted into Hufflepuff back in his day.
His magical ways roused suspicion, and he was eventually executed after the senior churchmen grew suspicious of his ability to cure the pox, and his penchant for pulling rabbits out of the Communion cup.
The Fat Friar always resented the fact that he never became a cardinal.
A hot-tempered sort of fellow, who was responsible for the death of the Grey Lady, aka Helena Ravenclaw. In his living days, he was simply known as The Baron. It was only at the point of his death that the 'bloody' part of his name was added in. And for good reason.
Head over heels in love with Helena Ravenclaw, The Baron murdered her out of anger when Helena refused to return home with him. After stabbing her fatally, he was so remorseful, he used the same weapon to take his own life.
The Bloody Baron's chains were an 'act of penitence' for what he did to Helena.
Well, that's the thing. Strictly speaking Peeves wasn't a ghost at all so we can't be sure. Think mischief-maker with a penchant for 'kinetic disturbances'. We do know that he reflects his nature, a seamless blend of humour and malice.
Who knows? We're not even sure he was ever alive like the other house ghosts, but many attempts have been made to remove Peeves from Hogwarts. One such attempt in 1876 went disastrously wrong and led to the whole school being evacuated.
Peeves was named for being the pet-peeve of every Hogwarts caretaker ever. Also – 'poltergeist' roughly means 'noisy ghost' in German. For more info on the little hoodlum, read here.