Their grandfather, Alec Horsley, was the founder of Northern Foods, and their father replaced him as chairman of the company from 1970 until the role was assumed by Christopher Haskins.

[2] According to Horsley's autobiography, Dandy in the Underworld, his birth name was Marcus, but his mother had decided to change it to Sebastian by the time she had returned from the hospital.

In an interview Horsley's mother gave to The Sunday Times, she admitted that her son's childhood was profoundly difficult: "I don't think Nicholas ever went to bed sober and I was always in a fog.

"[5] In 1983, Horsley married Evlynn Anne Smith (8 September 1962 – 18 April 2003), the daughter of a Scottish painter and decorator, and who, together with Meriel Scott, constituted the art and furniture-design company Precious McBane.

A sign on the door once read: "THIS IS NOT A BROTHEL / THERE ARE NO PROSTITUTES AT THIS ADDRESS",[11] as doorways on the street were often used by scammers to trick punters out of money, inevitably leading to angry confrontations with the innocent occupants.

A film and photos of the event, as well as his subsequent paintings of crosses, were exhibited in London in 2002;[12] the nails used for the crucifixion are currently on display in The Viktor Wynd Museum of Curiosities, Fine Art & Natural History[13] together with his red sequinned suit by Richard Anderson of Savile Row and other ephemera.

In an editorial article in The Observer in 2004, he described his preference for sex with prostitutes: "What I hate with women generally is the intimacy, the invasion of my innermost space, the slow strangulation of my art."

A one-man play, Dandy in the Underworld, written and directed by Tim Fountain opened at the Soho Theatre in London on 15 June 2010, one day before Horsley's death.

Following his death, in 2012 many of his personal items were turned into relics and exhibited and sold at The Last Tuesday Society's Gallery Viktor Wynd Fine Art.

A customs official said that "...travellers who have been convicted of a crime involving moral turpitude (which includes controlled-substance violations) or admit to previously having a drug addiction are not admissible...".

At the inquest on 17 August 2010 the Westminster Coroner, Dr Paul Knapman, decided that "[Horsley] was known to have abused drugs and to that extent he has been the author of his own misfortune.