In July 1816.
Lord Byron, Mary Wollstonecraft Godwin, Percy Bysshe Shelley & John Polidori, who have gathered at the Villa Diodati by Lake Geneva in a rainy Switzerland in this 'Year Without a Summer', tell each other tales. This spawns two classic Gothic narratives, Mary Shelley's Frankenstein and Polidori's The Vampyre. Byron also writes the poem Darkness.
Frankenstein
https://gutenberg.org/ebooks/41445
The Vampyre
https://gutenberg.org/ebooks/6087