Writing takes a lot of focus - here are a few authors who got rid of all sorts of distractions, including their clothes, while writing:

When Victor Hugo [wiki], the famous author of great tomes such as Les Misérables and The Hunchback of Notre-Dame, ran into a writer's block, he concocted a unique scheme to force himself to write: he had his servant take all of his clothes away for the day and leave his own nude self with only pen and paper, so he'd have nothing to do but sit down and write.

Ernest Hemingway [wiki] did not only write A Farewell to Arms, he also said farewell to clothes! The inside dirt is that Hemingway wrote nude, standing up, with his typewriter about waist level. Indeed, there might be a nudist streak in the Hemingway genes: Ernest's cousin Edward Hemingway opened Britain's oldest nudist colony, a nine-bedroom chateau called Metherell Towers, back in the 1930s!

Perhaps it's not so surprising that D.H. Lawrence [wiki], who wrote the controversial (and censored) erotic book Lady Chatterley's Lover, liked to climb mulberry trees, in the nude, before coming down to write.

James Whitcomb Riley [wiki], America's "Hoosier Poet," had his friends lock him up in a hotel room to write, naked, so he wouldn't be tempted to go down to the bar for a drink.

French poet and author Edmond Rostand [wiki], who is best known for his play Cyrano de Bergerac, was so sick of being interrupted by his friends that he took up working naked in his bathtub.