The Shelleys left Britain in 1818 for Italy, where their second and third children died before Shelley gave birth to her last and only surviving child, Percy Florence Shelley. In 1816, the couple famously spent a summer with Lord Byron, John William Polidori and Claire Clairmont near Geneva, Switzerland, where Shelley conceived the idea for her novel Frankenstein.

They married in late 1816, after the suicide of Percy Shelley's first wife, Harriet. Over the next two years, she and Percy faced ostracism, constant debt and the death of their prematurely born daughter. Upon their return to England, Shelley was pregnant with Percy's child. Together with her stepsister, Claire Clairmont, she and Percy left for France and travelled through Europe. In 1814, Shelley began a romance with one of her father's political followers, Percy Bysshe Shelley, who was already married. When she was four, her father married a neighbour with whom Shelley came to have a troubled relationship. She was raised by her father who was able to provide her with a rich if informal education, encouraging her to adhere to his own anarchist political theories. Shelley's mother died less than a month after giving birth to her. Her father was the political philosopher William Godwin and her mother was the philosopher and feminist Mary Wollstonecraft. She also edited and promoted the works of her husband, the Romantic poet and philosopher Percy Bysshe Shelley. She was raised by her father who was able to provide her with a rich if informal education, encouraging her to adhere to his Mary Wollstonecraft Shelley, née Godwin (30 August 1797 – 1 February 1851) was an English novelist who wrote the Gothic novel Frankenstein or, The Modern Prometheus (1818). Mary Wollstonecraft Shelley, née Godwin (30 August 1797 – 1 February 1851) was an English novelist who wrote the Gothic novel Frankenstein or, The Modern Prometheus (1818).

Mary wollstonecraft godwin shelley