At 18 years old, Mary Shelley crafted the idea of Frankenstein while reading, telling, and writing ghost stories with her husband, poet Percy Bysshe Shelley, her step sister Claire Clairmont, their friend Lord Byron, and Lord Byron’s physician, John Polidori, while trapped inside on a rainy day in Geneva, Switzerland in 1816. They were on a vacation at Lake Geneva, and the weather kept them trapped inside for days. To cope with their emotions while confined by the rain, they read horror stories together and found inspiration for their own ghost stories.Thus, the story of Frankenstein was born. 

The first edition was published anonymously out of fear of backlash on January 1, 1818 in London, but the second edition published in Paris in 1821 contained Shelley's name. The image included depicts the publishing company in London of the first edition of Frankenstein called Lackington, Hughes, Harding, Mavor and Jones. Since then, there have been many publications and iterations of the story, and there have also been numerous film adaptations of Frankenstein.

Sources:

Blakemore, Erin. “'Frankenstein' Was Born during a Ghastly Vacation 200 Years Ago.” History.com, A&E Television Networks, 9 Mar. 2018, https://www.history.com/news/frankenstein-true-story-mary-shelley.

Exploringlondon. “10 Sites from Mary Shelley's London...5. the Temple of the Muses, Finsbury Square...” Exploring London, 10 Oct. 2018, https://exploring-london.com/2018/10/10/10-sites-from-mary-shelleys-lond....

“Mary Shelley's ‘Frankenstein’ Is Published.” History.com, A&E Television Networks, 13 Nov. 2009, https://www.history.com/this-day-in-history/frankenstein-published.